Search results for " Inbred CBA"
showing 10 items of 42 documents
Comparative pharmacological activity of optical isomers of phenibut
2007
Phenibut (3-phenyl-4-aminobutyric acid) is a GABA (gamma-aminobutyric acid)-mimetic psychotropic drug which is clinically used in its racemic form. The aim of the present study was to compare the effects of racemic phenibut and its optical isomers in pharmacological tests and GABAB receptor binding studies. In pharmacological tests of locomotor activity, antidepressant and pain effects, S-phenibut was inactive in doses up to 500 mg/kg. In contrast, R-phenibut turned out to be two times more potent than racemic phenibut in most of the tests. In the forced swimming test, at a dose of 100 mg/kg only R-phenibut significantly decreased immobility time. Both R-phenibut and racemic phenibut showed…
The effect of cyclosporin A, FK506 and rapamycin on the murine contact sensitivity reaction
1998
We have evaluated the effects of three potent immunosuppressive agents, cyclosporin A (CsA), FK506 and rapamycin, on the murine contact sensitivity (CS) reaction to the hapten trinitrochlorobenzene. Development of CS reaction requires participation of three distinct T cell subsets: alphabeta+, CD4+ T lymphocytes, which are the classical effector cell of the CS reaction, gammadelta+ T lymphocytes, and alphabeta+, double-negative (CD4- CD8-) T lymphocytes that express the B220 molecule and produce IL-4. We found that all three drugs inhibit the development of the CS reaction, but they affect different target cells. In fact, rapamycin and FK-506 block both alphabeta+, CD4+ and gammadelta+ T ly…
Oral administration of pharmacological doses of Vitamins C and E reduces reproductive fitness and impairs the ovarian and uterine functions of female…
2002
This study aims to ascertain whether oral administration of pharmacological doses of Vitamins C and E has any detrimental effect on reproductive fitness of female mice. We fed hybrid female mice from the first day of weaning a standard diet supplemented or not supplemented with pharmacological doses of Vitamins C and E. At the age of 28 weeks, we individually caged females with a male for the rest of their reproductive life. We performed a series of mating experiments to ascertain the number of oocytes ovulated and the potential for embryo development in vitro to the blastocyst stage and in vivo to Day 12 of gestation. The antioxidant diet decreased the frequency of litters, litter size, to…
Identification and properties of the cell membrane bound leucine aminopeptidase interacting with the potential immunostimulant and chemotherapeutic a…
1983
Bestatin was found to be a competitive inhibitor (with respect to the Leu-NA substrate) not only of the isolated microsomal and cytosolic leucine aminopeptidases (Leu-APm and Leu-APc) but also of the aminopeptidases (APs) present in membrane preparations (from mouse liver) and on the cell surface of L5178Y cells. Kinetic parameters indicate that cellular AP is identical to Leu-APm. To rule out the possibility that AP-B is involved in the inhibition reactions, comparable studies with amastatin were performed. Electrophoretical studies revealed the solubilized cell membrane bound AP to co-migrate with Leu-APm in polyacrylamide gels. The activity of the separated membrane AP was inhibited by b…
Dietary antioxidant supplementation did not affect declining sperm function with age in the mouse but did increase head abnormalities and reduced spe…
1998
The present study aims to ascertain whether dietary administration of a mixture of vitamins C and E may prevent the negative effects of paternal age on male fertility variables in the mouse. Experimental males were fed a standard diet supplemented with either a low or high dose of vitamins C and E. Oocytes enclosed in cumulus masses were inseminated using a 2 x 2 factorial design established according to whether males were young (3-4 months of age) or aged (22-24 months of age) and whether they were fed a control or antioxidant diet. Aged males showed a significant decrease in number of spermatozoa/mg epididymis when compared to young males. Dietary supplementation with low doses of vitamin…
Effect of dietary supplementation with a mixture of Vitamins C and E on fertilization of tertiary butyl hydroperoxide-treated oocytes and parthenogen…
2002
The present study aims to analyze the effect of dietary supplementation with a mixture of Vitamins C and E on fertilization and later development of tertiary butyl hydroperoxide (tBH)-treated mouse oocytes and on parthenogenetic activation of freshly ovulated mouse oocytes. We fed hybrid mice a standard diet supplemented or not supplemented with Vitamins C and E from the first day of weaning until the age of 12 weeks. We noted no significant effect of diet on fertilization rate, percentage of total and hatching blastocysts, total number of cells, mitotic index and percentage of apoptotic nuclei at 120 h post-insemination of oocytes incubated for 15 min in the presence of 0, 1, 5 and 10 micr…
Antioxidant therapy counteracts the disturbing effects of diamide and maternal ageing on meiotic division and chromosomal segregation in mouse oocytes
1998
This study aims (i) to ascertain whether oxidative-stress-induced disturbances in chromosomal distribution in the metaphase-II spindle of mouse oocytes can be counteracted by supplementing culture medium with antioxidants; and (ii) to determine whether supplemental intake of antioxidants neutralizes the disturbing effects of maternal ageing on segregation of chromosomes during the first meiotic division and distribution of chromosomes in the metaphase-II spindle. (i): Germinal vesicle oocytes from unstimulated 10-12 week old mice were matured in vitro in the presence or absence of diamide and/or dithiothreitol. Metaphase-II oocytes were fixed and stained with 4',6-diamidino-2-phenylindole (…
Protective effect of adenylate deaminase (from Penicillium lanoso-viride) against acute infections in mice
1996
We examined the effects of the immunomodulator-adenylate deaminase (E.C. 3.5.4.6) from Penicillium lanoso-viride on experimental mice infections. Prophylactic intraperitoneal administration of adenylate deaminase (ADA) increased survival time and numbers of survivors after infection with Salmonella typhimurium, Pseudomonas aeruginosa and influenza A (H3N2) virus. Protection against influenza virus after intranasal ADA application was also observed. The influence of ADA was time and dose dependent. The most pronounced protection was obtained by administration of 3 U ADA/mice 24 h prior to infection. ADA had no antibiotic effect against these bacterial strains. Protective effects of ADA were …
TCR V alpha chain expression influences reactivity to the hapten TNP.
1997
We have recently demonstrated a remarkable selection of in vitro cultivated, TNP-specific polyclonal T cell lines for the expression of a TCR beta chain encoded by the V beta 8.2 gene. The goal of the present study was to analyse V alpha usage in V beta 8.2 T cells responsive to TNP, using TNP-specific T cell lines derived from three common strains of mice, as well as from V beta 8.2 transgenic mice. Results indicate that in vitro TNP stimulation of T cells from TNP-immune mice results in significant skewing of V alpha usage among responding V beta 8.2+ T cells, with overexpression observed for V alpha 3.2 and V alpha 8. These results indicate that V alpha expression influences recognition …
T-cell-mediated cytotoxicity against herpes simplex virus-infected target cells
1977
THE control of herpes simplex virus (HSV) infection by immunological mechanisms seems to be complex and is poorly understood. Neutralising antibodies to HSV plus complement seem to have no effect on the propagation of HSV infection, because HSV spreads to adjacent cells by passing through intercellular bridges1–3. Anti-HSV antibodies plus complement, however, destroy virus-infected cells, but cannot prevent the spread of HSV, suggesting that the virus must be transferred to neighbouring cells before immune lysis occurs1,5. Therefore if lymphocyte-mediated cytolytic mechanisms are instrumental in blocking the spread of HSV in vivo, they ought to destroy infected cells at a very early stage i…