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Secretory Products (secretory + products)
Selected AbstractsSecretory products of the haptoral reservoirs and peduncular glands in two species of Bravohollisia (Monogenea: Ancyrocephalidae)INVERTEBRATE BIOLOGY, Issue 2 2008Wey-Lim Wong Abstract. Light and electron microscopy were used to characterize the structure of secretory cells and their products involved in attachment of two monogenean parasites of fish, in order to understand their role in the attachment process. In Bravohollisia rosetta and Bravohollisia gussevi, peduncular gland cells with two nuclei, granular endoplasmic reticulum, and Golgi bodies produce dual electron-dense (DED) secretory bodies with a homogenous electron-dense rind and a less electron-dense fibrillar core (oval and concave in B. rosetta and oval in B. gussevi). The DED secretory bodies are altered as they migrate from the gland cell to the haptoral reservoir, the superficial anchor grooves, and into the gill tissues. The contents of the DED secretory bodies are exocytosed into the reservoirs, fibrillar cores persisting in the matrix, some of which condense, forming highly electron-dense spherical bodies. Small, oval, electron-dense bodies occur in the grooves, while no inclusions are visible in the homogenous exudate within the gill tissues. The single tubular extension of the reservoir enters a bifurcate channel within the anchor via a concealed, crevice-like opening on one side of the anchor. The channel directs secretions into the left and the right grooves via concealed apertures. The secretions, introduced into the tissues by the anchors, probably assist in attachment. The secretions are manifested externally as net-like structures and observed in some cases to be still attached to the point of exudation, on anchors detached from the gill tissues. This suggests that despite having the anchors detached, the worms can still remain anchored to the gill tissues via these net-like structures. Based on this, it is postulated that the net-like secretions probably function as a safety line to anchor the worm during the onset of locomotion and in doing so reduce the risk of tearing host tissues. [source] Reproduction in male rats is vulnerable to treatment with the flavonoid-rich seed extracts of Vitex negundoPHYTOTHERAPY RESEARCH, Issue 1 2004Suwagmani Das Abstract A partially puri,ed ,avonoid-rich extract was prepared from the seed of Vitex negundo. The effect of this extract on the reproductive system of male rats was investigated at four different concentrations. All the major accessory sex organs shed weight when the preparation was administered at doses of ,15 mg/rat/day after 15 days of treatment. The drop in weight was also re,ected in disturbed tissue biochemistry. Secretory products such as citric acid in the prostate, fructose in seminal vesicles and epididymal , -glucosidase activity, indices of accessory sex organ function in males, diminished. Microscopic examination of the sperm derived from the cauda epididymides of treated animals showed only a marginal change in vitality. However, sperm numbers dwindled and slackness in their motility was observed, factors that may impede fertility. Toxicity testing in blood did not point to distress in any of the vital organs. Taken together, it is inferred that the seed extracts of V. negundo interfere with male reproductive function without producing adverse toxicity in other vital organs. Copyright © 2004 John Wiley & Sons, Ltd. [source] The secreted and surface proteomes of the adult stage of the carcinogenic human liver fluke Opisthorchis viverriniPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 5 2010Jason Mulvenna Abstract Infection with the human liver fluke, Opisthorchis viverrini, is a serious public health problem in Thailand, Laos and nearby locations in Southeast Asia. Both experimental and epidemiological evidence strongly implicate liver fluke infection in the etiology of one of the liver cancer subtypes, cholangiocarcinoma (CCA). To identify parasite proteins critical for liver fluke survival and the etiology of CCA, OFFGEL electrophoresis and multiple reaction monitoring were employed to characterize 300 parasite proteins from the O. viverrini excretory/secretory products and, utilizing selective labeling and sequential solubilization, from the host-exposed tegument. The excretory/secretory included a complex mixture of proteins that have been associated with cancers, including proteases of different mechanistic classes and orthologues of mammalian growth factors and anti-apoptotic proteins. Also identified was a cysteine protease inhibitor which, in other helminth pathogens, induces nitric oxide production by macrophages, and, hence may contribute to malignant transformation of inflamed cells. More than 160 tegumental proteins were identified using sequential solubilization of isolated teguments, and a subset of these was localized to the surface membrane of the tegument by labeling living flukes with biotin and confirming surface localization with fluorescence microscopy. These included annexins, which are potential immuno-modulators, and orthologues of the schistosomiasis vaccine antigens Sm29 and tetraspanin-2. Novel roles in pathogenesis were suggested for the tegument,host interface since more than ten surface proteins had no homologues in the public databases. The O. viverrini proteins identified here provide an extensive catalogue of novel leads for research on the pathogenesis of opisthorchiasis and the development of novel interventions for this disease and CCA, as well as providing a scaffold for sequencing the genome of this fluke. [source] On the hunt for helminths: innate immune cells in the recognition and response to helminth parasitesCELLULAR MICROBIOLOGY, Issue 9 2008Jacqueline G. Perrigoue Summary The generation of protective immunity to helminth parasites is critically dependent upon the development of a CD4+ T helper type 2 cytokine response. However, the host,parasite interactions responsible for initiating this response are poorly understood. This review will discuss recent advances in our understanding of how helminth-derived products are recognized by innate immune cells. Specifically, interactions between helminth excretory/secretory products and host Toll-like receptors and lectins will be discussed as well as the putative functions of helminth proteases and chitin in activating and recruiting innate immune cells. In addition, the functional significance of pattern recognition by epithelial cells, granulocytes, dendritic cells and macrophages including expression of alarmins, thymic stromal lymphopoetin, interleukin (IL)-25, IL-33 and Notch ligands in the development of adaptive anti-parasite Th2 cytokine responses will be examined. [source] Changes in the oviducal epithelium during the estrous cycle in the marsupial Monodelphis domesticaJOURNAL OF ANATOMY, Issue 4 2007Annetrudi Kress Abstract The Monodelphis oviduct can be divided into four anatomical segments: preampulla (comprising fimbriae and infundibulum), ampulla, isthmus with crypts and uterotubal junction. Ovaries are enclosed in a periovarial sac, the bursa, and in some specimens tubules of an epoophoron could be identified. In both structures non-ciliated cells develop small translucent vesicles, which accumulate in the cell apices and presumably produce fluid as often seen in the bursa and in the tubules of the epooophoron. These vesicles do not stain with Alcian blue or PAS. The same applies also to the non-ciliated cells of the fimbriae. The oviducal epithelium of ampulla and the surface epithelium of the isthmus consisting of ciliated and non-ciliated, secretory cells undergo considerable changes during the estrous cycle. Proestrus shows low numbers of ciliated cells, some are in the process of neo-ciliogenesis, non-ciliated cells carry solitary cilia and few remnant secretory granules from the previous cycle may be found. At estrus the amount of ciliated cells in ampulla and isthmus has increased, most non-cililated cells lost the solitary cilia, developed longer microvilli and formed numerous secretory granules in their cell apices. At postestrus secretory products, often surrounded by membranes, are extruded into the oviducal lumen and contribute towards egg coat formation. First signs of deciliation processes are apparent. Solitary cilia reappear. At metestrus only few secretory cells are left with some secretory material. The lumen is often filled with shed cilia and cell apices. Proliferation of basal bodies within non-secretory cells indicate the formation of new ciliated cells. The non-ciliated epithelial cells of the isthmic crypts form no secretory granules but accumulate a great number of translucent vesicles, which in contrast to the secretory granules do not stain with Alcian blue or PAS. [source] Secretion of RANTES (CCL5) and interleukin-10 from mesenteric adipose tissue and from creeping fat in Crohn's disease: Regulation by steroid treatmentJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 9 2006Andreas Schäffler Abstract Background:, Creeping fat represents a characteristic feature of Crohn's disease (CD) and adipose tissue is currently being recognized as a complex compartment secreting highly active molecules. Pro- or anti-inflammatory adipose tissue-derived secretory products (adipocytokines) might play a role in the pathogenesis of CD. Methods:, Adipose tissue specimens were obtained from creeping fat contiguous to the involved intestine of 10 patients with CD. Mesenteric adipose tissue specimens resected in 13 patients with colon cancer (CC) and in seven patients with diverticulitis (DIV) served as controls. Three fat tissue specimens per well and n = 6,8 wells per patient were incubated ex vivo for 24 h. The release of regulated on activation, T-cell expressed and secreted (RANTES) and interleukin (IL)-10 into the supernatant was measured by ELISA. Results:, Both RANTES and IL-10 secretion could be demonstrated from total adipose tissue explants. The RANTES secretion is increased from creeping fat in CD (3691 ± 597 pg/g fat per 24 h) when compared to mesenteric adipose tissue from patients with CC (1690 ± 191 pg/g fat per 24 h; P < 0.0001) or DIV (1672 ± 336 pg/g fat per 24 h; P < 0.0001). In contrast, IL-10 secretion is downregulated significantly only in patients with DIV (1418 ± 180 pg/g fat per 24 h; P = 0.016) when compared to CC patients (2368 ± 259 pg/g fat per 24 h). Crohn's disease patients receiving steroids had a higher secretion rate of RANTES and IL-10. Conclusions:, Both RANTES and IL-10 secretion can be detected from mesenteric adipose tissue and from creeping fat. The elevated RANTES and IL-10 secretion from creeping fat in CD is not due to a CD-specific effect but caused by steroid treatment. [source] Fast and optimized T1 mapping technique for the noninvasive quantification of gastric secretionJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 1 2008Reto Treier MSc Abstract Purpose To evaluate the noninvasive quantification of gastric secretion volume after administration of a labeled viscous glucose solution by fast T1 mapping. Materials and Methods T1 values of a series of labeled and diluted glucose solutions were measured in vitro to characterize the interrelationship between T1 and contrast agent concentration (CGd) as well as the dependency of relaxivity and reference T1 (T10) on the macromolecular concentration. Abdominal T1 mapping in five healthy volunteers of different body mass index was performed after filling an intragastric balloon with a labeled and diluted glucose solution. In additional ex vivo experiments, T1 values of gastric (GJ) and duodenal juice (DJ) and 0.1 N HCl solution were determined. Results A linear relationship between relaxivity and macromolecular concentration and between T10 and macromolecular concentration was found. The in vitro T1,CGd calibration curve was successfully validated in all volunteers. T1 values of GJ, DJ, and HCl (2939 msec vs. 2858 msec vs. 2760 msec) were close to the T1 of water (,3000 msec). Conclusion The presented method allows one to noninvasively quantify the spatial distribution of gastric secretory products in the human stomach and provides a valuable tool for evaluating the efficacy of drugs to stimulate/inhibit gastric secretion. J. Magn. Reson. Imaging 2008;28:96,102. © 2008 Wiley-Liss, Inc. [source] Human immunodeficiency virus type 1 gp120 inhibits long-term potentiation via chemokine receptor CXCR4 in rat hippocampal slicesJOURNAL OF NEUROSCIENCE RESEARCH, Issue 3 2006Jun Dong Abstract Human immunodeficiency virus type 1 (HIV-1) infection in its human host often results in progressive dementia and encephalopathy in adults and children, respectively. The mechanisms underlying virus-induced neurocognitive dysfunction are not fully understood. However, several studies strongly suggest that secretory viral and immune products from infected brain macrophages and microglia affect the onset and tempo of disease. One critical neurotoxin among these secretory products is the HIV-1 envelope glycoprotein gp120. To better understand how HIV-1 gp120 may affect cognitive function, we studied its effects on long-term potentiation (LTP) in the CA1 region of rat hippocampus, the brain region best linked to learning and memory. Although no effects were observed on basal synaptic transmission, HIV-1 gp120 inhibited LTP in a concentration-dependent manner in the presence of ,-aminobutyric acid type A (GABAA) receptor antagonist. Heat-inactivated gp120 failed to block LTP. The HIV-1 gp120-mediated LTP inhibition was blocked by T140, a chemokine receptor CXCR4 antagonist, demonstrating gp120 inhibition of LTP via CXCR4. HIV-1 gp120 V3 loop peptides mimicked the inhibitory effects of HIV-1 gp120 protein on LTP. Monoclonal antibodies against the V3 loop epitope KRIHI eliminated the HIV-1 gp120 effects on LTP. These results further underscore the importance of HIV-1 gp120 in the pathogenesis of HIV-1-associated cognitive impairments seen during progressive viral infection. © 2006 Wiley-Liss, Inc. [source] Postoperative serum attenuates LPS-induced release of TNF-, in orthopaedic surgeryJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 10 2007Olav Reikerås Abstract Studies with ex vivo stimulation of whole blood samples from injured patients have revealed a diminished production capacity for a broad range of secretory products, including inflammatory cytokines. Recent interest has focused on the release of mediators in serum that depress the cell-mediated immune response following trauma. The involvement of the lipid mediator prostaglandin E2 (PGE2) has been assumed because it is a potent endogenous immunosuppressor. In the present study, we tested the hypothesis that inhibitory substances circulating in the patient's serum after a major musculoskeletal trauma might impair leukocyte function by evaluating the effect of such serum on cytokine release in a whole blood model. Six females and three males undergoing elective total hip replacement were included in the study. Ex vivo LPS-induced TNF-, and IL-10 were measured in whole blood sampled preoperatively and added serum taken before, at the end of operation, and at postoperative days 1 and 6 with saline as negative control. LPS induced significant releases of TNF-, and IL-10 in whole blood. Addition of preoperative, postoperative, and day-1 postoperative serum did not alter the LPS-induced release of TNF-, as compared to saline. In the presence of serum from postoperative day 6, however, the expression of TNF-, was significantly reduced as compared to saline and preoperative serum (p,=,0.021 and 0.008, respectively). Neither of the serum samples altered the release of IL-10. PGE2 was significantly (p,=,0.008) increased in serum at postoperative day 6 as compared to preoperative levels. In conclusion, these data show that at day 6 after major orthopaedic surgery, the patient serum contained activity that inhibited ex vivo LPS-induced TNF-, release. The potent TNF-, inhibitory activity found at day 6 after injury correlated with increased levels of PGE2 and indicates cell-mediated hyporesponsiveness to a second stimulus. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:1395,1400, 2007 [source] Sex Differences in Ethanol-Induced Hypothermia in Ethanol-Naïve and Ethanol-Dependent/Withdrawn RatsALCOHOLISM, Issue 1 2009Anna N. Taylor Background:, Human and animal findings indicate that males and females display major differences in risk for and consequences of alcohol abuse and alcoholism. These differences are in large part mediated by sex-specific hormonal environments. Gonadal and adrenal secretory products are known to modulate the neurobehavioral responses of ethanol (EtOH) dependence and withdrawal. However, the effects of these steroids on physiological adaptations, such as thermoregulation, are less well established. To study the role of sex-related hormones in mediating sex differences in the hypothermic response to acute challenge with EtOH, we compared the EtOH-induced hypothermic responses of EtOH-naïve male and female rats and EtOH-dependent (on the third day of withdrawal) male and female rats before (intact) and after depletion of all gonadal and adrenal steroids by gonadectomy (GDX) with or without adrenalectomy (ADX). Methods:, Intact and GDX male and female rats, with or without ADX, were fed an EtOH-containing liquid diet for 15 days while control (EtOH-naïve) rats were pairfed the isocaloric liquid diet without EtOH or fed normal rat chow and water. On the third day of withdrawal from the EtOH diet we tested the hypothermic response to EtOH challenge (1.5 g/kg BWt, ip). Blood alcohol content (BAC) and corticosterone (CORT) content were analyzed in a separate series of intact and GDX males and females with and without ADX in response to the EtOH challenge. Results:, Ethanol-induced hypothermia was significantly greater and its duration significantly longer in intact males than females when subjects were EtOH-naïve. EtOH-induced hypothermia was significantly greater in intact females than males by the third day of withdrawal from EtOH dependence. GDX in males significantly shortened the duration of the hypothermic response and tended to blunt EtOH-induced hypothermia while response duration was significantly extended by GDX in females that tended to enhance EtOH-hypothermia. EtOH-induced hypothermia was significantly enhanced and its duration significantly lengthened by combined GDX and ADX in EtOH-naïve and -withdrawn males and by combined GDX and ADX in EtOH-naïve but not EtOH-withdrawn females. These differential EtOH-induced hypothermic responses did not appear to be caused by differences in EtOH handling among the groups. The absence of adrenal activation by EtOH in the GDX,ADX males and females contributes to their enhanced EtOH-induced hypothermic responses. Conclusions:, These results implicate the direct and indirect effects of removal of gonadal and adrenal secretory products as mediators of the thermoregulatory actions of EtOH. [source] Gene for porcine pregnancy-associated glycoprotein 2 (poPAG2): Its structural organization and analysis of its promoter,MOLECULAR REPRODUCTION & DEVELOPMENT, Issue 2 2001Bozena Szafranska Abstract The pregnancy-associated glycoproteins (PAG) are abundant secretory products of the placental trophectoderm of ungulate species. They are structurally related to pepsin, having the capability to bind peptides. However, many cannot function as enzymes due to amino acid substitutions in and around the catalytic site. Here, we demonstrate that pigs, like cattle and sheep, but unlike equids, have multiple PAG genes. One of the transcribed porcine PAG (poPAG) genes, the one for poPAG2, was cloned. It had a nine-exon organization similar to that of other mammalian aspartic proteinase genes with an atypical TATA sequence. A total of 1.2 kbp upstream from exon 1 was sequenced. This region shared identity (>,65%) with the promoter regions of the bovine (bo) PAG1, boPAG2 and equine (eq) PAG genes, but not with other aspartyl proteinase genes, including that of pepsinogen A. Nor were there clear similarities to the promoters of other genes with trophoblast-specific expression. Of the different poPAG2 promoter constructs tested in transfection experiments in two human (JAr and JEG3) and one rat (Rcho) choriocarcinoma cell lines, only the shortest (,149 bp) was required to provide full expression of a luciferase reporter. Although this short promoter was not active in Cos-1 and L-929 cells, it was active in CHO cells, a transformed non-trophoblast hamster ovarian cell line. Co-transfection of Ets2 elevated the activity of this short promoter approximately six-fold in JAr cells, but, disruption of the two putative Ets sites did not alter the ability of Ets2 to transactivate the promoter. In the non-trophoblast cell lines, Ets2 failed to elicit any response. Ets2 responsiveness may be a common feature of most or all trophoblast-expressed genes, although in the case of poPAG2, the effect may be indirect. Mol. Reprod. Dev. 60: 137,146, 2001. © 2001 Wiley-Liss, Inc. [source] Antigen selection for future anti- Trichuris vaccines: a comparison of cytokine and antibody responses to larval and adult antigen in a primary infectionPARASITE IMMUNOLOGY, Issue 9 2008H. DIXON SUMMARY Trichuriasis, caused by the whipworm Trichuris trichiura, is endemic in tropical and subtropical areas, affecting approximately 1 billion people. Child anthelminthic treatment programmes are being implemented but repeated treatments are costly, may prevent the development of acquired immunity and can lead to the development of drug resistant parasites. Thus, the development of a vaccine which would lead to the acquisition of immunity at an earlier age and reduce community faecal egg output would be beneficial. Development of subunit vaccines requires the identification of protective antigens and their formulation in a suitable adjuvant. Trichuris muris is an antigenically similar laboratory model for T. trichiura. Subcutaneous vaccination with adult excretory,secretory products (ES) protects susceptible mouse strains from T. muris. Larval stages may contain novel and more relevant antigens which when incorporated in a vaccine induce worm expulsion earlier in infection than the adult worm products. This study finds negligible difference in the cellular and humoral immune response to T. muris adult and third stage larva(e) (L3) ES during a primary T. muris infection, but identifies high molecular weight proteins in both adult and L3 ES as potential vaccine candidates. [source] Molluscan and vertebrate immune responses to bird schistosomesPARASITE IMMUNOLOGY, Issue 7-8 2005P. HORÁK SUMMARY There is a growing understanding of risks posed by human contact with the cercariae of bird schistosomes. In general, there are no fundamental biological differences between human and bird schistosomes in terms of their interactions with snail and vertebrate hosts. The penetration of host surfaces is accompanied by the release of penetration gland products and the shedding of highly antigenic surface components (miracidial ciliated plates and cercarial glycocalyx) which trigger host immune reactions. New surface structures are formed during transformation: the tegument of mother sporocysts and the tegumental double membrane of schistosomula. These surfaces apparently serve as protection against the host immune response. Certain parasite excretory,secretory products may contribute to immunosuppression or, on the other hand, stimulation of host immune reactions. Discovery of new species and their life cycles, the characterization of host,parasite interactions (including at the molecular level), the determination of parasite pathogenicity towards the host, the development of tools for differential diagnosis and the application of protective measures are all topical research streams of the future. Regularly updated information on bird schistosomes and cercarial dermatitis can be found at http://www.schistosomes.cz (web pages of Schistosome Group Prague). [source] Protection in lambs vaccinated with Haemonchus contortus antigens is age related, and correlates with IgE rather than IgG1 antibodyPARASITE IMMUNOLOGY, Issue 1 2000Kooyman Protection by vaccination with excretory,secretory products (ES) from Haemonchus contortus, containing predominantly proteins of 15 and 24 kDa, against an experimental challenge infection depends on the age of the sheep. Vaccinated sheep 9, 6 or 3 months of age were protected for 83%, 77% and ,34%, respectively. There was a significant difference in ES-specific serum IgE response but not in IgG1 response, after the last vaccination between the different age groups. In the protected 9-month-old animals, there was an increase up to 18 times the prevaccination levels, while the increase in the unprotected 3-month-old animals was at most 1.4 times. The 6-month-old animals showed an intermediate increase of approximately six times the prevaccination level. There was no correlation within the 9-month-old sheep between ES-specific IgE levels and protection, measured as worm burden. However, when the different age groups were combined, there was a positive correlation (r = 0.38) between protection and ES-specific IgE levels 1 week after the vaccination. At the end of the experiment, peripheral blood eosinophils and mast cell counts in abomasal tissue were also significantly higher in the vaccinated and challenged 9-month-old sheep than in the vaccinated and challenged 3-month-old or than in the 9-month-old sheep with challenge, but without vaccination. Increased serum IgE levels, eosinophilia and mucosal mast cell hyperplasia are the hallmarks of a Th2 response and were all demonstrated in protected, older sheep, but not in unprotected, younger sheep. [source] Elevated serum progastrin-releasing peptide (31,98) in metastatic and androgen-independent prostate cancer patients,THE PROSTATE, Issue 2 2002Masahiro Yashi Abstract BACKGROUND Increases in neuroendocrine phenotype and secretory products are closely correlated with tumor progression and androgen independence in prostate cancer. In this study, we explored this correlation using serum progastrin-releasing peptide (ProGRP), a carboxy-terminal region common to three subtypes of precursors for gastrin-releasing peptide (GRP), which is released from the neuroendocrine phenotype to act as a growth factor. METHODS In 60 patients with benign prostatic hyperplasia (BPH) and 200 with prostate cancer, serum ProGRP levels were determined with an enzyme-linked immunosorbent assay (ELISA) kit and evaluated in relation to clinical stage, hormonal treatment, and prostate-specific antigen (PSA) values. Fourteen randomly selected patients were entered in the follow-up study. Additionally, expression of ProGRP as determined by immunohistochemical analysis was compared to that of chromogranin-A (CgA) in tissue samples from several subjects. RESULTS We found a positive correlation between PSA and ProGRP in patients with untreated prostate cancer; no correlation was found in the treated groups. The increases in the ProGRP value and in the percentage of patients with higher than normal values were significant (P,<,0.0001), especially in the androgen-independent group (P,<,0.0001). A longitudinal study showed that, in a subset of patients, the ProGRP values tended to increase transiently when the cancer became androgen independent, but remained unchanged or decreased at the androgen-dependent stage. Positive staining for ProGRP occurred in a different distribution in neuroendocrine tissues than that of staining for CgA. CONCLUSIONS The clinical results demonstrated the existence of a regulatory mechanism for GRP, which to date had only been observed in cell lines. These findings suggest that GRP is a growth factor potentially upregulated by androgen but that does not rely principally on androgen modulation. The large overlap in levels of ProGRP among the groups limits the use of this value as a monitoring tool. Measurement of ProGRP, however, does have potential as an independent parameter to evaluate androgen-independent progression and to facilitate a new therapeutic strategy that may compensate for current limitations of diagnosis based on PSA alone. Prostate 51: 84,97, 2002. © 2002 Wiley-Liss, Inc. [source] Juvenile hormone,stimulated synthesis of acyl-glycerols and vitamin E in female accessory sexual glands of the fire bug, Pyrrhocoris apterus L.ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY (ELECTRONIC), Issue 1 2009Pavel Jedli Abstract Secretory cells of the female accessory sexual glands (AG) of P. apterus grow and produce yellow oily exocrine secretion in response to stimulation by endogenous juvenile hormone (JH) or exogenous treatments by JH analogues. The secretion determines the property of future egg shells by coating the chorion surface of the oocytes that are passing individually through the common uterus during oviposition. Diapausing females with a physiologically inhibited endocrine system or females with artificially removed hormonal sources show inactive ovaries and empty AG without the secretory products. Ovary-ectomised females with the intact neuroendocrine system develop hypertrophic AG loaded with the oily secretion. This shows that there is no direct dependence between formation of the oily secretion in AG and ovarian growth. Chemical analysis of the secretory products revealed the presence of acetylated glycerols, with the most abundant stearoyl-diacetyl-glycerol, stearoyl-acetyl-propionyl-glycerol, and the corresponding derivatives of arachidonic acid. In addition to this, the JH-activated secretory cells of AG also produced , - and , -tocopherols. The possible antioxidant or antimutagenic action of these vitamin E compounds in insect reproduction has been emphasized. © 2009 Wiley Periodicals, Inc. [source] | ||||||||||||||||