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Laboratory Rat (laboratory + rat)
Selected AbstractsExperimental model of heterotopic uterus transplantation in the laboratory ratMICROSURGERY, Issue 3 2003Lucian P. Jiga M.D. The present study describes a standardized experimental model of whole-uterus-and-ovaries heterotopic allotransplantation in the laboratory rat. Fifteen transplantation procedures were done. The anatomy of the pelvic region was studied with an additional 20 dissections, noting the topographical and vascular anatomy of the uterus, fallopian tubes, and ovarian vessels. Recipients were randomized into three groups. The average operative time was 150 min. The postoperative survival rate was 100%. Postoperative vascular anastomosis patency was 100%, and 26% at 72 hr. Recipients were euthanized at 24 hr (group I), 48 hr (group II), and 72 hr (group III); grafts were harvested and examined macroscopically, and fixed in formaline for histopathological and immunocytochemical analysis. Failure in 74% of the grafts at 72 hr was due to early thrombosis, starting from the capillary bed and progressing towards the main feeding pedicles. More studies must be undertaken to further understand the rejection mechanisms in transplanted reproductive organs. The efficiency, feasibility, and safety for such an operation in humans remain to be proven. We consider the present model a suitable tool to study all the above-mentioned goals. © 2003 Wiley-Liss, Inc. MICROSURGERY 23:246,250 2003 [source] Detection of ,2u -globulin and its bound putative pheromones in the preputial gland of the Indian commensal rat (Rattus rattus) using mass spectrometryRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 6 2010R. Rajkumar The role of pheromones and pheromone-binding proteins in the laboratory rat has been extensively investigated. However, we have previously reported that the preputial gland of the Indian commensal rat produces a variety of pheromonal molecules and preputial glands would seem to be the predominant source for pheromonal communication. The presence of pheromone-binding proteins has not yet been identified in the preputial gland of the Indian commensal rat; therefore, the experiments were designed to unravel the ,2u -globulin (,2u) and its bound volatiles in the commensal rat. Total preputial glandular proteins were first fractionated by sodium dodecyl sulfate/polyacrylamide gel electrophoresis (SDS-PAGE) and subsequently analyzed by mass spectrometry. Further, we purified ,2u and screened for the presence of bound pheromonal molecules with the aid of gas chromatography/mass spectrometry (GC/MS). A novel ,2u was identified with a high score and this protein has not been previously described as present in the preputial gland of Indian commensal rats. This novel ,2u was then characterized by tandem mass spectrometry (MS/MS). Peptides with m/z values of 969, 1192, 1303 and 1876 were further fragmented with the aid of MS/MS and generated denovo sequences which provided additional evidence for the presence of ,2u in the preputial gland. Finally, we identified the presence of farnesol 1 and 2 bound to ,2u. The present investigation confirms the presence of ,2u (18.54,kDa) in the preputial gland of the Indian commensal rat and identifies farnesol 1 and 2 as probably involved in chemo-communication by the Indian commensal rat. Copyright © 2010 John Wiley & Sons, Ltd. [source] A Note on Langerhans Cells in the Oesophagus Epithelium of Domesticated MammalsANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 2 2010W. Meyer With 3 figures Summary Using the zinc-iodide osmium tetroxide (ZIO) method, TEM and immunohistochemistry (for CD1a and langerin), the study demonstrates Langerhans cells in the oesophageal epithelium of domesticated mammals (herbivores: horse, cattle, goat; omnivores: pig, dog, laboratory rat; carnivores: cat), although with variations between the species. The ZIO method and TEM showed this cell type in the cat and, sporadically, in the horse; CD1a (+) Langerhans cells were demonstrated in the ovine, porcine and murine oesophagus. Positive staining for langerin was detected in single cells of the caprine, canine, murine and feline oesophagus and more distinct in almost all the cell layers of the equine and porcine oesophagus epithelium. The findings are discussed comparing specifically the results for CD1a and langerin, whereby the latter C-type lectin may be of importance in species with a rather thick oesophagus epithelium, such as that present in the plantivorous and most of the omnivorous animals, where antigenic pressure is reduced. [source] The effect of increased lipoprotein levels on the pharmacokinetics of cyclosporine A in the laboratory ratBIOPHARMACEUTICS AND DRUG DISPOSITION, Issue 1 2006Dion R. Brocks Abstract The response of cyclosporine A (CyA) blood concentrations following changes in lipoprotein levels have been inconsistent. Some studies show increases in concentrations, whereas others have shown decreases. The intent of this study was to examine the effect of two rat models of increased lipoprotein on the pharmacokinetics of CyA. One was a simulated high fat content meal, in which 1% cholesterol in peanut oil was administered. The other was the poloxamer 407-induced model of hyperlipidemia. Rats in these two groups were compared to a group fasted overnight before the study. In rats given a simulated high fat meal, at most time points the mean blood and plasma concentrations were lower, though not significantly, compared to fasted animals. Oral lipid led to no significant changes in the measured pharmacokinetic parameters of blood or plasma area under the concentration vs time curve (AUC), clearance (CL), volume of distribution (Vd) or plasma unbound fraction. In the poloxamer 407-treated hyperlipidemic rats there were significant reductions in plasma unbound fraction plasma, Vd and terminal half-life, but not AUC or CL, compared to normolipidemic rats. In contrast, the CL, Vd and t1/2 in the oral lipid-fed rats were all significantly higher than the poloxamer 407 treated animals. Oral absolute bioavailability of CyA was unchanged by oral lipid. In humans and rats the pharmacokinetics of CyA in the face of increased lipoprotein levels do not correspond well to what is typically seen for other drugs that are known to bind to lipoproteins. Copyright © 2005 John Wiley & Sons, Ltd. [source] MDMA, methamphetamine and their combination: possible lessons for party drug users from recent preclinical researchDRUG AND ALCOHOL REVIEW, Issue 1 2007KELLY J. CLEMENS Abstract The substituted amphetamines 3,4-methylenedioxymethamphetamine (MDMA, ,Ecstasy') and methamphetamine (METH, ,ice', ,speed') are increasingly popular drugs amongst party-drug users. Studies with humans have investigated the acute and possible long-term adverse effects of these drugs, yet outcomes of such studies are often ambiguous due to a variety of confounding factors. Studies employing animal models have value in determining the acute and long-term effects of MDMA and METH on brain and behaviour. Self-administration studies show that intravenous METH is a particularly potent reinforcer in rats and other species. In contrast, MDMA appears to have powerful effects in enhancing social behaviour in laboratory animals. Brief exposure to MDMA or METH may produce long-term reductions in dopamine, serotonin and noradrenaline in the brain and alterations in the density of various receptor and transporter proteins. However it is still unclear, particularly in the case of MDMA, whether this reflects a ,neurotoxic' effect of the drug. Lasting alterations in social behaviour, anxiety, depressive symptoms and memory have been demonstrated in laboratory rats given MDMA or METH and this matches long-term changes reported in some human studies. Recent laboratory studies suggest that MDMA/METH combinations may produce greater adverse neurochemical and behavioural effects than either drug alone. This is of some concern given recent evidence that party drug users may be frequently exposed to this combination of drugs. [source] Pelvic growth: Ontogeny of size and shape sexual dimorphism in rat pelvesJOURNAL OF MORPHOLOGY, Issue 1 2007S. Berdnikovs Abstract The mammalian pelvis is sexually dimorphic with respect to both size and shape. Yet little is known about the differences in postnatal growth and bone remodeling that generate adult sexual dimorphism in pelvic bones. We used Sprague-Dawley laboratory rats (Rattus norvegicus), a species that exhibits gross pelvic size and shape dimorphism, as a model to quantify pelvic morphology throughout ontogeny. We employed landmark-based geometric morphometrics methodology on digitized landmarks from radiographs to test for sexual dimorphism in size and shape, and to examine differences in the rates, magnitudes, and directional patterns of shape change during growth. On the basis of statistical significance testing, the sexes became different with respect to pelvic shape by 36 days of age, earlier than the onset of size dimorphism (45 days), although visible shape differences were observed as early as at 22 days. Males achieved larger pelvic sizes by growing faster throughout ontogeny. However, the rates of shape change in the pelvis were greater in females for nearly all time intervals scrutinized. We found that trajectories of shape change were parallel in the two sexes until age of 45 days, suggesting that both sexes underwent similar bone remodeling until puberty. After 45 days, but before reproductive maturity, shape change trajectories diverged because of specific changes in the female pelvic shape, possibly due to the influence of estrogens. Pattern of male pelvic bone remodeling remained the same throughout ontogeny, suggesting that androgen effects on male pelvic morphology were constant and did not contribute to specific shape changes at puberty. These results could be used to direct additional research on the mechanisms that generate skeletal dimorphisms at different levels of biological organization. J. Morphol., 2006. © 2006 Wiley-Liss, Inc. [source] Survival of Escherichia coli O157 in faeces of experimentally infected rats and domestic pigeonsLETTERS IN APPLIED MICROBIOLOGY, Issue 5 2000In order to evaluate the role of some synanthropic animals in the spreading of Escherichia coli O157, laboratory rats and domestic pigeons were experimentally infected per os with E. coli O157. Rats infected with 105 colony forming units (cfu) (n = 5) and 109 cfu (n = 5) shed E. coli O157 for 2 ± 1·7 d and 9·8 ± 1·3 d, respectively. In the faeces of infected rats stored at 4 °C in a moist environment, at 4 °C in a dry environment or at 20 °C in a moist environment, E. coli O157 survived for 34 weeks. When stored at 20 °C or ,,20 °C in a dry environment, E. coli O157 survived for , 36 weeks. Pigeons infected with 105 cfu (n = 5) and 109 cfu (n = 5) shed the pathogen for 14·8 ± 3·4 d and 20·2 ± 5·2 d, respectively. Both species, rats and pigeons can be important in spreading of the E. coli O157 infection in cattle. [source] Social behavior in laboratory rats: Applications for psycho-neuroethology studiesANIMAL SCIENCE JOURNAL, Issue 4 2006Yutaka YAMAMURO ABSTRACT The social behavior in laboratory animals occurs in conspecific groups. In the past two decades, the physiological basis of the social behavior in laboratory rats has been gradually elucidated through various neural approaches. In addition, the relevance of social related behavior for psycho-neuroethology studies has been extensively proposed. An analysis of social recognition behavior of new conspecifics is a useful approach for the study of memory without aversive alternatives such as fear, pain and anxiety. Furthermore, it is considered that artificial or experimental social isolation can induce altered emotional states in laboratory rats. This article reviews the past findings regarding social behavior and aspects of its expression, and discusses further possibilities for animal models of human neuro-psychiatric disorders. [source] | |||||||||||||