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Taste Buds (taste + bud)
Selected AbstractsMorphology of the Lingual Dorsal Surface and Oral Taste Buds in Italian Lizard (Podarcis sicula)ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 2 2010F. Abbate Summary With 4 figures The Italian lizard (Podarcis sicula) is the most diffused reptile in Italy, but it is also present in other European countries. This lizard belongs to the Lacertidae family, lives near walls, slants and along the borders of the paths; its diet includes bugs and aracnids. No data are so far available in literature about the three-dimensional morphology of the tongue of Podarcis sicula, therefore the aim of the present paper was to study by scanning electron and light microscopy the three-dimensional characteristics of the dorsal lingual surface and moreover the presence of chemosensory receptors like the taste buds in the oral cavity. Our results demonstrate that the Podarcis sicula tongue is a triangular muscular membranous organ, dorsoventrally flattened and that three different areas can be observed: a bifid apex, a body and a root. No papillae were observed in the apex, characterized by a flattened mucosa and by two deep median pouches. In the body cylindrical papillae with a flat surface are present, aborally gradually substituted by imbricated papillae. Foliate-like papillae were observed in the lateral parts of the tongue body. No sensory structures were showed on the lingual dorsal surface, while they were numerous in the oral cavity, particularly on the gingival epithelium. The light microscopy shows, on the dorsal surface, a stratified pavimentous not keratinized epithelium, conversely keratinized along the ventral surface. Many caliciform cells on the lateral parts of the papillae, deputed to the secretion of mucus, were also observed. Therefore, the results obtained in this paper could give a contribution to the knowledge of the tongue anatomy in a species widely diffused in different European countries and could be of help for clinical purposes in reptiles. [source] Optical recordings of taste responses from fungiform papillae of mouse in situTHE JOURNAL OF PHYSIOLOGY, Issue 2 2001Yoshitaka Ohtubo 1Single taste buds in mouse fungiform papillae consist of ,50 elongated cells (TBCs), where fewer than three TBCs have synaptic contacts with taste nerves. We investigated whether the non-innervated TBCs were chemosensitive using a voltage-sensitive dye, tetramethylrhodamine methyl ester (TMRM), under in situ optical recording conditions. 2Prior to the optical recordings, we investigated the magnitude and polarity of receptor potentials under in situ whole-cell clamp conditions. In response to 10 mM HCl, several TBCs were depolarized by ,25 mV and elicited action potentials, while other TBCs were hyperpolarized by ,12 mV. The TBCs eliciting hyperpolarizing receptor potentials also generated action potentials on electrical stimulation. 3A mixture of 100 mM NaCl, 10 mM HCl and 500 mM sucrose depolarized six TBCs and hyperpolarized another three TBCs out of 13 identified TBCs in a taste bud viewed by optical section. In an optical section of another taste bud, 1 M NaCl depolarized five TBCs and hyperpolarized another two TBCs out of 11 identified TBCs. 4The number of chemosensitive TBCs was much larger than the number of innervated TBCs in a taste bud, indicating the existence of chemosensitivity in non-innervated TBCs. There was a tendency for TBCs eliciting the same polarity of receptor potential to occur together in taste buds. We discuss the role of non-innervated TBCs in taste information processing. [source] Liposome-mediated transfection of mature taste cellsDEVELOPMENTAL NEUROBIOLOGY, Issue 1 2005Ana Marie Landin Abstract The introduction and expression of exogenous DNA in neurons is valuable for analyzing a range of cellular and molecular processes in the periphery, e.g., the roles of transduction-related proteins, the impact of growth factors on development and differentiation, and the function of promoters specific to cell type. However, sensory receptor cells, particularly chemosensory cells, have been difficult to transfect. We have successfully introduced plasmids expressing green and Discosoma Red fluorescent proteins (GFP and DsRed) into rat taste buds in primary culture. Transfection efficiency increased when delaminated taste epithelium was redigested with fresh protease, suggesting that a protective barrier of extracellular matrix surrounding taste cells may normally be present. Because taste buds are heterogeneous aggregates of cells, we used ,-gustducin, neuronal cell adhesion molecule (NCAM), and neuronal ubiquitin carboxyl terminal hydrolase (PGP9.5), markers for defined subsets of mature taste cells, to demonstrate that liposome-mediated transfection targets multiple taste cell types. After testing eight commercially available lipids, we identified one, Transfast, that is most effective on taste cells. We also demonstrate the effectiveness of two common "promiscuous" promoters and one promoter that taste cells use endogenously. These studies should permit ex vivo strategies for studying development and cellular function in taste cells. © 2005 Wiley Periodicals, Inc. J. Neurobiol, 2005 [source] Recovery of two independent sweet taste systems during regeneration of the mouse chorda tympani nerve after nerve crushEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 6 2007Keiko Yasumatsu Abstract In rodents, section of the taste nerve results in degeneration of the taste buds. Following regeneration of the cut taste nerve, however, the taste buds reappear. This phenomenon can be used to study the functional reformation of the peripheral neural system responsible for sweet taste. In this study we examined the recovery of sweet responses by the chorda tympani (CT) nerve after nerve crush as well as inhibition of these responses by gurmarin (Gur), a sweet response inhibitor. After about 2 weeks of CT nerve regeneration, no significant response to any taste stimuli could be observed. At 3 weeks, responses to sweet stimuli reappeared but were not significantly inhibited by Gur. At 4 weeks, Gur inhibition of sweet responses reached statistically significant levels. Thus, the Gur-sensitive (GS) component of the sweet response reappeared about 1 week later than the Gur-insensitive (GI) component. Moreover, single CT fibers responsive to sucrose could be classified into distinct GS and GI groups at 4 weeks. After 5 weeks or more, responses to sweet compounds before and after treatment with Gur became indistinguishable from responses in the intact group. During regeneration, the GS and GI components of the sucrose response could be distinguished based on their concentration-dependent responses to sucrose. These results suggest that mice have two different sweet-reception systems, distinguishable by their sensitivity to Gur (the GS and GI systems). These two sweet-reception systems may be reconstituted independently during regeneration of the mouse CT nerve. [source] STG does not associate with psoriasis in the Swedish populationEXPERIMENTAL DERMATOLOGY, Issue 7 2004Fabio Sánchez Abstract:, Psoriasis is a chronic inflammatory skin disease that is known to have a strong genetic predisposition. Several psoriasis-susceptibility loci have been previously found through genomic scans. Of these, psoriasis-susceptibility region 1 (PSORS1) on chromosome 6p21 remains the most consistently identified region across populations with the highest association with disease. STG is a gene that was previously isolated from rhesus monkey taste buds, and its ortholog in humans was found to be part of the cluster of genes in PSORS1, which is telomeric to HLA-C. Upon characterization of STG, we identified several sequence variants and investigated their association with psoriasis in cases and controls from the Swedish population. None of these STG single-nucleotide polymorphisms were found to be significantly associated with psoriasis. However, HLA-Cw*0602 status was strongly associated with disease. STG expression was investigated in human tissues and found not to be restricted to taste buds, with signals also being detected in skin and tonsils. [source] Perception of sweet taste is important for voluntary alcohol consumption in miceGENES, BRAIN AND BEHAVIOR, Issue 1 2008Y. A. Blednov To directly evaluate the association between taste perception and alcohol intake, we used three different mutant mice, each lacking a gene expressed in taste buds and critical to taste transduction: ,-gustducin (Gnat3), Tas1r3 or Trpm5. Null mutant mice lacking any of these three genes showed lower preference score for alcohol and consumed less alcohol in a two-bottle choice test, as compared with wild-type littermates. These null mice also showed lower preference score for saccharin solutions than did wild-type littermates. In contrast, avoidance of quinine solutions was less in Gnat3 or Trpm5 knockout mice than in wild-type mice, whereas Tas1r3 null mice were not different from wild type in their response to quinine solutions. There were no differences in null vs. wild-type mice in their consumption of sodium chloride solutions. To determine the cause for reduction of ethanol intake, we studied other ethanol-induced behaviors known to be related to alcohol consumption. There were no differences between null and wild-type mice in ethanol-induced loss of righting reflex, severity of acute ethanol withdrawal or conditioned place preference for ethanol. Weaker conditioned taste aversion (CTA) to alcohol in null mice may have been caused by weaker rewarding value of the conditioned stimulus (saccharin). When saccharin was replaced by sodium chloride, no differences in CTA to alcohol between knockout and wild-type mice were seen. Thus, deletion of any one of three different genes involved in detection of sweet taste leads to a substantial reduction of alcohol intake without any changes in pharmacological actions of ethanol. [source] Structural diversification of the gustatory organs during metamorphosis in the alpine newt Triturus alpestrisJOURNAL OF ANATOMY, Issue 3 2007Krystyna Abstract Gustatory organs of the taste bud type occur in the epithelial lining of the oropharyngeal cavity of alpine newt larvae. They resemble the taste buds of bony fish, both in appearance (as revealed by scanning electron microscopy) and in detailed internal structure (seen on transmission electron micropscopy). During metamorphosis, at stage 55 of development, the secondary tongue (i.e. the soft tongue) is well formed and the anlages of taste discs are clearly apparent. Somewhat later, taste discs also appear in the epithelial lining outside the tongue, paralleling the disappearance of the taste buds. Well-developed taste discs of the newt differ from taste buds mainly by their structurally diversified set of ,associate cells' (mucous, wing and glial cells), which have no synaptic contact with nerve fibres. These cells accompany the neurosensory cellular components of the taste disc, i.e. the taste receptor cells and basal cells. This indicates that gustatory organs in metamorphosed newts, regardless of their small dimensions, fulfil the criteria established for taste discs previously defined in other Caudata and Anura species. Therefore, in the development of the newt there are two subsequent types of gustatory organs and two generations of the tongue: primary, in the larvae, and secondary, in metamorphosed animals. [source] On the vascularization and structure of the skin of a Korean bullhead Pseudobagrus brevicorpus (Bagridae, Teleostei) based on its entire body and appendagesJOURNAL OF APPLIED ICHTHYOLOGY, Issue 1 2010J. Y. Park Summary To investigate the vascularization and structure of the skin and its relationship to cutaneous respiration in Pseudobagrus brevicorpus, a histological study by light microscopy was carried out on 15 regions of the skin, including eight body regions, six fins and the barbel. The skin consisted of the epidermis, dermis and subcutis in all regions, except for the barbel that had a relatively thin dermis and subcutis. The epidermis was composed of the outermost layer, the middle layer and the stratum germinativum. There were two kinds of gland cells: the unicellular mucus cells and large club cells. The middle layer had a small number of fine blood capillaries accompanied by dermal collagen in all regions; the mean number of blood capillaries ranged from 0.9 to 5.9. The mean diffusion distance between the capillary endothelial cells and the surface of the epidermis ranged from 50.6 to 126.8 ,m. Based on these intra-epithelial blood capillaries, the relative surface area of the respiratory epithelium ranged from 0.1 to a maximum value of 1.2%. The dermis lacking scales had collagen bundles arranged parallel to each other, but vertical fiber bundles around the dorso-lateral regions were seen at intervals. Sensory organs such as taste buds, pit organs and lateral canals were found whereby the taste buds in particular were more abundant in the epidermis of the barbel. The vascularization of the skin may be closely related to an additional respiratory system used to deal with an extreme hypoxic condition during dry seasons. [source] Do G protein-coupled receptors expressed in human lingual epithelium interact with HPV11?JOURNAL OF MEDICAL VIROLOGY, Issue 10 2007Lukasz Durzy Abstract Human papillomaviruses infect epithelia but little is known about the nature of cell surface receptors interacting with the viral particles. It has been proposed that glycosaminoglycans and integrins may be involved in the attachment process. In the present study, the putative interactions of virus-like particles of human papillomavirus type 11 (HPV11), which present a tropism for nasopharyngeal epithelia, with olfactory and taste receptors expressed in the human lingual epithelium were studied. The L1 protein of HPV11 was produced in insect cells. The presence of L1 virus-like particles was analyzed by ELISA using monoclonal antibodies specific for full-size particles and by electron microscopy. Using immunofluorescence, it was observed that virus-like particles interacted with taste buds from murine tongue, with the tagged human olfactory receptor hJCG5 expressed in HEK-293 but not with the tagged taste receptor hT2R4. This therefore suggests that hJCG5 may be involved in the adsorption process of HPV11 to lingual epithelium serving as a so-called "adsorption-adhesive molecule." J. Med. Virol. 79:1545,1554, 2007. © Wiley-Liss, Inc. [source] Comparative morphology and cytology of the male sperm-transmission organs in viviparous species of clinid fishes (Clinidae: Teleostei, Perciformes)JOURNAL OF MORPHOLOGY, Issue 12 2006Lev Fishelson Abstract This work comprises the first comparative study of the morphology and cytology of the sperm transmission organs in males of 14 species of viviparous clinid fishes (Clinidae, Blennioidei, Teleostei). The form and dimensions of these organs differ among the various species studied. The organs are composed of intra-abdominal ampullae, into which the sperm ducts and urinary bladder anchor, and an external protruding intromittent papilla used for insemination. The form of the ampullae differs among the various species, from pear-shaped to horseshoe-shaped. It increases in dimensions with increasing length of the male. In all the species this organ is covered by a connective-tissue tunic that encompasses both circular and longitudinal striated muscle bundles. The lumina of the ampullae harbor the epididymis, a strongly convoluted and plicated duct, which becomes filled with spermatozeugmata during reproduction. From here, the epididymis continues into the protruding intromittent papillae, where its folds gradually straighten at the apical part of the intromittent organ. The form and dimensions of this copulatory organ also differ in the various species. Papillae bearing taste buds are found on the apical parts of the intromittent organ, and it is probable that these, together with the difference in forms of the organ, help to prevent interspecific copulation. J. Morphol., 2006. © 2006 Wiley-Liss, Inc. [source] Ultrastructural study of the precursor to fungiform papillae prior to the arrival of sensory nerves in the fetal ratJOURNAL OF MORPHOLOGY, Issue 3 2001Shin-ichi Iwasaki Abstract The structure of precursors to fungiform papillae without taste buds, prior to the arrival of sensory nerve fibers at the papillae, was examined in the fetal rat on embryonic day 13 (E13) and 16 (E16) by light and transmission electron microscopy in an attempt to clarify the mechanism of morphogenesis of these papillae. At E13, a row of rudiments of fungiform papillae was arranged along both sides of the median sulcus of the lingual dorsal surface, and each row consisted of about 10 rudiments. There was no apparent direct contact between papillae rudiments and sensory nerves at this time. Bilaterally towards the lateral side of the tongue, adjacent to these first rudiments of fungiform papillae, a series of cord-like invaginations of the dorsal epithelium of the tongue into the underlying connective tissue, representing additional papillary primordia parallel to the first row, was observed. The basal end of each invagination was enlarged as a round bulge, indented at its tip by a mound of fibroblasts protruding into the bulge. At E16 there was still no apparent direct contact between rudiments of fungiform papillae and sensory nerves. Each rudiment apically contained a spherical core of aggregating cells, which consisted of a dense assembly of large, oval cells unlike those in other areas of the lingual dorsal epithelium. The differentiation of these aggregated cells was unclear. The basal lamina was clearly recognizable between the epithelium of the rudiment of fungiform papillae and the underlying connective tissue. Spherical structures, which appeared to be sections of the cord-like invaginations of the lingual epithelium that appeared on E13, were observed within the connective tissue separated from the dorsal lingual epithelium. Transverse sections of such structures revealed four concentric layers of cells: a central core, an inner shell, an outer shell, and a layer of large cells. Bundles of fibers were arranged in the central core, and the diameters of bundles varied somewhat depending on the depth of the primordia within the connective tissue and their distance from the median sulcus. Ultrastructural features of cells in the outer shell differed significantly in rudiments close to the lingual epithelium as compared to those in deeper areas of connective tissue. Around the outer shell there was a large-cell layer consisting of one to three layers of radially elongated, oval cells that contained many variously sized, electron-dense, round granules. Large numbers of fibroblasts formed dense aggregates around each spherical rudiment, and were separated by the basal lamina from the large-cell epithelial layer. Progressing from deep-lying levels of the rudiments of the papillae to levels close to the lingual surface epithelium, the central core, inner shell, and outer shell gradually disappeared from the invaginated papillary cords. J. Morphol. 250:225,235, 2001. © 2001 Wiley-Liss, Inc. [source] Rodlet cells and the sensory systems in zebrafish (Danio rerio)THE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 4 2007Bahram Sayyaf Dezfuli Abstract This preliminary work was designed to study, using routine procedures for light and transmission electron microscopy, the presence of rodlet cells (RCs) in or near the sensory systems of 12 adult specimens (4.0 ± 1.2 cm, LT ± SD) of zebrafish, Danio rerio Hamilton, 1822. Rodlet cells, characterized by a distinctive cell cortex (range, 0.4,1.5 ,m in thickness) and conspicuous inclusions named "rodlets," have a round to ovoid nucleus with irregular outline. Mature RCs are 11.5 ± 1.2 ,m (mean ± SD) long and 7.8 ± 1.1 ,m (mean ± SD) wide. These cells are more numerous near neuromasts enclosed by an epithelial roof and/or ossified canal wall. In contrast, very few RCs were noticed near superficial neuromasts. Based on the presence of RCs around the two cranial neuromasts of each fish, a variable number from 1 to 15 rodlet cells was found (10.4 ± 3.6, mean ± SD). The RCs were located 1.5 ,m (minimal) to 73.3 ,m (maximal) from the neuromast (27.9 ± 17.2, mean ± SD). Moreover, RCs were found in olfactory epithelium and in proximity to some taste buds. Interestingly, RCs were absent in the inner ear, eye, and brain. Anat Rec, 2007. © 2007 Wiley-Liss, Inc. [source] Group IIA phospholipase A2 is coexpressed with SNAP-25 in mature taste receptor cells of rat circumvallate papillaeTHE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 6 2006Hideaki Oike Abstract The taste buds are composed of heterogeneous cell populations with diverse properties and at different stages of maturity. It is important to define the relationships between cell properties and cell maturity to understand the molecular events involved in intracellular taste signaling. In the present study, in situ hybridization analysis indicated that group IIA phospholipase A2 (PLA2 -IIA) is expressed in a subset of taste bud cells. Immunohistochemical studies showed that PLA2 -IIA was expressed in a subset of cells expressing phospholipase C,2, a molecule essential for taste signaling in taste receptor cells, and also that some PLA2 -IIA-positive cells expressed gustducin (Ggust), a bitter-taste-signaling molecule. Although PLA2 -IIA and Ggust were expressed at similar frequencies in taste buds, bromodeoxyuridine (BrdU) chase experiments indicated that the expression of Ggust began 2 days after BrdU injection, whereas the expression of PLA2 -IIA commenced after 4 days. In addition, PLA2 -IIA was coexpressed with SNAP-25, a synaptosomal-associated protein. These results indicated that PLA2 -IIA is expressed in mature taste receptor cells that possess exocytotic machinery. J. Comp. Neurol. 494:876,886, 2006. © 2005 Wiley-Liss, Inc. [source] In vivo recordings from rat geniculate ganglia: taste response properties of individual greater superficial petrosal and chorda tympani neuronesTHE JOURNAL OF PHYSIOLOGY, Issue 3 2005Suzanne I. Sollars Coding of gustatory information is complex and unique among sensory systems; information is received by multiple receptor populations located throughout the oral cavity and carried to a single central relay by four separate nerves. The geniculate ganglion is the location of the somata of two of these nerves, the greater superficial petrosal (GSP) and the chorda tympani (CT). The GSP innervates taste buds on the palate and the CT innervates taste buds on the anterior tongue. To obtain requisite taste response profiles of GSP neurones, we recorded neurophysiological responses to taste stimuli of individual geniculate ganglion neurones in vivo in the rat and compared them to those from the CT. GSP neurones had a distinct pattern of responding compared to CT neurones. For example, a small subset of GSP neurones had high response frequencies to sucrose stimulation, whereas no CT neurones had high response frequencies to sucrose. In contrast, NaCl elicited high response frequencies in a small subset of CT neurones and elicited moderate response frequencies in a relatively large proportion of GSP neurones. The robust whole-nerve response to sucrose in the GSP may be attributable to relatively few, narrowly tuned neurones, whereas the response to NaCl in the GSP may relate to proportionately more, widely tuned neurones. These results demonstrate the diversity in the initial stages of sensory coding for two separate gustatory nerves involved in the ingestion or rejection of taste solutions, and may have implications for central coding of gustatory quality and concentration as well as coding of information used in controlling energy, fluid and electrolyte homeostasis. [source] Optical recordings of taste responses from fungiform papillae of mouse in situTHE JOURNAL OF PHYSIOLOGY, Issue 2 2001Yoshitaka Ohtubo 1Single taste buds in mouse fungiform papillae consist of ,50 elongated cells (TBCs), where fewer than three TBCs have synaptic contacts with taste nerves. We investigated whether the non-innervated TBCs were chemosensitive using a voltage-sensitive dye, tetramethylrhodamine methyl ester (TMRM), under in situ optical recording conditions. 2Prior to the optical recordings, we investigated the magnitude and polarity of receptor potentials under in situ whole-cell clamp conditions. In response to 10 mM HCl, several TBCs were depolarized by ,25 mV and elicited action potentials, while other TBCs were hyperpolarized by ,12 mV. The TBCs eliciting hyperpolarizing receptor potentials also generated action potentials on electrical stimulation. 3A mixture of 100 mM NaCl, 10 mM HCl and 500 mM sucrose depolarized six TBCs and hyperpolarized another three TBCs out of 13 identified TBCs in a taste bud viewed by optical section. In an optical section of another taste bud, 1 M NaCl depolarized five TBCs and hyperpolarized another two TBCs out of 11 identified TBCs. 4The number of chemosensitive TBCs was much larger than the number of innervated TBCs in a taste bud, indicating the existence of chemosensitivity in non-innervated TBCs. There was a tendency for TBCs eliciting the same polarity of receptor potential to occur together in taste buds. We discuss the role of non-innervated TBCs in taste information processing. [source] Electrical Taste Thresholds Established on the Medial Tongue using Two Sizes of Electrodes,THE LARYNGOSCOPE, Issue 8 2005Serban A. Nicolaescu BS Abstract Objectives/Hypothesis: The present study determined whether a 125 mm2 electrode would produce lower and more reliable electrical taste thresholds than a 25 mm2 electrode when measurement occurred in a medial tongue region relatively sparse in taste bud numbers. We hypothesized this would be the case and that the obtained threshold values would be higher than those previously reported for anterior and lateral tongue regions. Study Design And Methods: Sixteen college-age subjects were tested twice, once using the 25 mm2 electrode and once using the 125 mm2 electrode on each of two sessions separated by 2 to 16 days. The order of presentation of the sessions was counterbalanced across subjects. Measurement was confined to the medial tongue, 0.7 cm lateral to the median furrow. Results: As hypothesized, the larger electrode resulted in lower and more reliable threshold values than the smaller electrode (respective median threshold values = 20.06 ,A & 33.59 ,A, P = .001; respective test-retest rs = 0.78 [P < .001] and 0.46 [P < .05]). Also as hypothesized, the threshold values were higher (i.e., sensitivity lower) than previously reported for anterior and lateral tongue regions. Conclusions: The magnitude and reliability of electrical taste thresholds depends on the tongue region examined and the size of the electrodes used. These results suggest that relatively large electrodes should be considered for electrogustometric threshold testing, particularly when lingual regions not highly populated with taste buds are evaluated. [source] Morphology of the Lingual Dorsal Surface and Oral Taste Buds in Italian Lizard (Podarcis sicula)ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 2 2010F. Abbate Summary With 4 figures The Italian lizard (Podarcis sicula) is the most diffused reptile in Italy, but it is also present in other European countries. This lizard belongs to the Lacertidae family, lives near walls, slants and along the borders of the paths; its diet includes bugs and aracnids. No data are so far available in literature about the three-dimensional morphology of the tongue of Podarcis sicula, therefore the aim of the present paper was to study by scanning electron and light microscopy the three-dimensional characteristics of the dorsal lingual surface and moreover the presence of chemosensory receptors like the taste buds in the oral cavity. Our results demonstrate that the Podarcis sicula tongue is a triangular muscular membranous organ, dorsoventrally flattened and that three different areas can be observed: a bifid apex, a body and a root. No papillae were observed in the apex, characterized by a flattened mucosa and by two deep median pouches. In the body cylindrical papillae with a flat surface are present, aborally gradually substituted by imbricated papillae. Foliate-like papillae were observed in the lateral parts of the tongue body. No sensory structures were showed on the lingual dorsal surface, while they were numerous in the oral cavity, particularly on the gingival epithelium. The light microscopy shows, on the dorsal surface, a stratified pavimentous not keratinized epithelium, conversely keratinized along the ventral surface. Many caliciform cells on the lateral parts of the papillae, deputed to the secretion of mucus, were also observed. Therefore, the results obtained in this paper could give a contribution to the knowledge of the tongue anatomy in a species widely diffused in different European countries and could be of help for clinical purposes in reptiles. [source] The Lingual Dorsal Surface of the Blue-Tongue Skink (Tiliqua scincoides)ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 5 2009F. Abbate Summary The blue-tongue lizard (Tiliqua scincoides) is a variety of large skink common throughout Australia. There are seven species of Tiliqua and all of them have long bodies, short limbs and short and robust tails. T. scincoides occurs in a wide range of habitats; its diet is omnivorous. When threatened, it opens the mouth and protrudes its characteristic large fleshy cobalt blue tongue. It is currently found as a popular species and also as a pet animal in the European countries. No data are available in literature about the morphology of the tongue of T. scincoides; therefore, the aim of the present study was to investigate by means of scanning electron microscopy and light microscopy, the anatomy of the dorsal lingual surface. Our results demonstrate the presence of a tongue tip with a smooth surface without papillae. The foretongue was characterized by a stratified epithelium with foliate-like papillae and deep inter-papillar spaces in the middle part and cylindrical papillae with a flat surface in the lateral parts. All the posterior area of the tongue was characterized by more compacted papillae and the inter-papillar spaces were very narrow. Light microscopy showed the presence of melanin throughout the tongue. No taste buds were recognized on the lingual dorsal surface. Therefore, the papillae probably have a mechanical function showing an important role in the swallowing phase. The morphology of the tongue surface can be correlated to the diet and, different roles, as in other examined species, can be hypothesized for different areas. [source] Morphology and Morphometry of Lingual Papillae in Adult and Newborn Egyptian Fruit Bats (Rousettus aegyptiacus)ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 5 2009J. Trzcieli, ska-Lorych Summary The paper presents a comparison of the microscopic structure and morphometric traits of gustatory and mechanical lingual papillae in newborn and adult frugivorous Egyptian fruit bats (Rousettus aegyptiacus). All of the four types of lingual papillae found in adult animals were observed on the tongue surface in the newborn Egyptian fruit bats. After the birth, the gustatory papillae (fungiform and vallate papillae) were especially well-developed, as their structural characteristics, such as morphology of the epithelium and presence of the taste buds, indicate that they have reached almost complete functional traits. Mechanical papillae, particularly filiform papillae, in newborns are still fetal in character. Keratinization processes in the epithelium of these papillae are not advanced and specific structures, such as elongated processes, are missing. The morphometric analysis of the size of papillae and thickness of the mucosal epithelium showed that a complete development of keratinized structures in Egyptian fruit bats occurs at later stages of postnatal development. [source] Characteristics of Filiform, Fungiform and Vallate Papillae and Surface of Interface Epithelium-Connective Tissue of the Maned Sloth Tongue Mucosa (Bradypus torquatus, Iliger, 1811): Light and Scanning Electron Microscopy StudyANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 1 2009E. J. Benetti Summary The study of lingual surfaces and the surface of interface epithelium-connective tissue of the tongue of Bradypus torquatus was performed by employing the light and scanning electron microscopy (SEM) techniques. The results revealed that the rostral part of the tongue presents a round apex and covered by filiform and fungiform lingual papillae and a ventral smooth surface. It was observed that the epithelial layer of the dorsal surface possesses the basal, spinosum, granular and cornified epithelial cells. The lamina propria is characterized by a dense connective tissue forming the long, short and round papillae. Numerous typical filiform papillae are located especially in the rostral part intermingled for few fungiform papillae, which were revealed in three-dimensional SEM images. Usually, the fungiform papillae are located in the border of rostral apex of the tongue exhibiting the rounded form. They are covered by keratinized epithelial cells. In the fungiform papillae, several taste pores were observed on the surface. The vallate papillae presented numerous taste buds in the wall of epithelial cells, being that the major number of taste buds is located on the superior half of vallate papilla. The taste pores are surrounded by several laminae of keratinized epithelial cells. The samples treated with NaOH solution and examined by SEM revealed, after removal of the epithelial layer, the dense connective core in original disposition, presenting different sizes and shapes. The specimens stained with Picrosirius and examined by polarized light microscopy revealed the connective tissue, indicating the collagen fibres type I and type III. [source] Scanning Electron Microscopical Study of the Lingual Epithelium of Green Iguana (Iguana iguana)ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 4 2008F. Abbate Summary During the last few years, green iguanas (Iguana iguana) have turned out to be one of the most popular pets. They are omnivorous. In their way of feeding, this crucial function is performed by capturing of the preys and mostly, this is carried out by the tongue. The role of the tongue is also fundamental during the intra-oral transport and during the swallowing of food. This has been reported in several studies about chameleons, agamids and iguanids, nevertheless published data about the mechanisms of capturing and swallowing the prey, and the morphological descriptions about the tongue epithelium, are scarce. Therefore, the aim of this present study was to analyse the morphology of the lingual epithelium in green iguanas by scanning electron microscopy. Three different areas were demonstrated on the tongue surface: the tongue tip, characterized by a smooth epithelium without papillae, a foretongue, completely covered by numerous closely packed cylindriform papillae, and a hindtongue with conical-like papillae. Some taste buds were recognized on the middle and the posterior parts of the tongue. Different functional roles could be hypothesized for the three tongue areas: the tongue tip could have a role related to the movements of the prey immediately after the capturing, while the middle papillae and the hindtongue could have an important role concerning the swallowing phase. [source] The number of taste buds is related to bitter taste sensitivity in layer and broiler chickensANIMAL SCIENCE JOURNAL, Issue 2 2010Ken-ichi KUDO ABSTRACT The relationship between taste sensitivity and the number of taste buds using a bitter tastant, quinine hydrochloride, was investigated in White Leghorn, Rhode Island Red, and broiler chickens. The White Leghorn and Rhode Island Red strains were able to perceive 2.0 mmol/L quinine hydrochloride, but the taste sensitivity of Rhode Island Red chickens was higher than that of White Leghorn chickens. Broiler chickens perceived 0.5 mmol/L quinine hydrochloride. The number of taste buds in the White Leghorn strain was the lowest, then the Rhode Island Red strain, with the number of taste buds highest in the broiler chickens. The number of taste buds was well correlated with bitter taste sensitivity. Therefore, we suggest that the number of taste buds is a vital factor in the perception of bitter taste and may be useful in selecting appropriate feeds for chickens. [source] Nutritional regulation of intestine morphology in larval cyprinid fish, silver bream (Vimba vimba)AQUACULTURE RESEARCH, Issue 12 2008Teresa Ostaszewska Abstract The present study includes the evaluation of morphological changes in the digestive tract of larval, stomachless fish silver bream (Vimba vimba) fed with various diets , live Artemia nauplii, commercial feed Aglo Norse (NOR) and semi-purified formulated diets: casein,gelatin (CG), dipeptide-protein (50P), dipeptide (100P), no-arginine dipeptide diet (100Pw/oArg) and a free amino acid (FAA) mixture diet. The supranuclear area of enterocytes in the posterior intestine contained enlarged absorptive vacuoles in the FAA, 100P and 100Pw/oArg groups, compared with the remaining groups. Hepatocytes' cytoplasm in fish fed with FAA, 100P and 100Pw/oArg contained mainly glycogen, and no lipid vacuoles were found. Fish fed with 100Pw/oArg showed the lowest hepatocyte surface areas while in those fed with 50P, the largest nuclei diameters were observed. Fish fed with Artemia, NOR and CG diets showed significantly (P<0.05) higher number of proliferating cells compared with the remaining groups. Chromogranin A staining showed endocrine-immunoreactive cells (CgA-IR) in the taste buds in the oral cavity and in the enterocytes' supranuclear areas of the anterior and posterior intestine. We conclude that the growth rate and histological examination of the digestive tract in the 50P group of silver bream showed no nutritional deficiency. [source] | ||||||||||||||||||||||||||||