Search results for "inbred c57bl"
showing 10 items of 1287 documents
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…
Opposite role played by GABAA and GABAB receptors in the modulation of peristaltic activity in mouse distal colon.
2014
We investigated the role of GABA on intestinal motility using as model the murine distal colon. Effects induced by GABA receptors recruitment were examined in whole colonic segments and isolated circular muscle preparations to analyze their influence on peristaltic reflex and on spontaneous and neurally-evoked contractions. Using a modified Trendelenburg set-up, rhythmic peristaltic contractions were evoked by gradual distension of the colonic segments. Spontaneous and neurally-evoked mechanical activity of circular muscle strips were recorded in vitro as changes in isometric tension. GABA, at low concentrations (10-50 µM), potentiated peristaltic activity and the neural cholinergic contrac…
Cannabinoid type 1 receptor blockade promotes mitochondrial biogenesis through endothelial nitric oxide synthase expression in white adipocytes
2008
OBJECTIVE—Cannabinoid type 1 (CB1) receptor blockade decreases body weight and adiposity in obese subjects; however, the underlying mechanism is not yet fully understood. Nitric oxide (NO) produced by endothelial NO synthase (eNOS) induces mitochondrial biogenesis and function in adipocytes. This study was undertaken to test whether CB1 receptor blockade increases the espression of eNOS and mitochondrial biogenesis in white adipocytes. RESEARCH DESIGN AND METHODS—We examined the effects on eNOS and mitochondrial biogenesis of selective pharmacological blockade of CB1 receptors by SR141716 (rimonabant) in mouse primary white adipocytes. We also examined eNOS expression and mitochondrial biog…
Elevation of striatal urate in experimental models of Parkinson's disease: a compensatory mechanism triggered by dopaminergic nigrostriatal degenerat…
2014
Epidemiological studies have indicated an inverse association between high uricemia and incidence of Parkinson's disease (PD). To investigate the link between endogenous urate and neurotoxic changes involving the dopaminergic nigrostriatal system, this study evaluated the modifications in the striatal urate levels in two models of PD. To this end, a partial dopaminergic degeneration was induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in mice, while a severe dopaminergic degeneration was elicited by unilateral medial forebrain bundle infusion of 6-hydroxydopamine (6-OHDA) in rats. Urate levels were measured by in vivo microdialysis at 7 or 14 days from toxin exposure. The resu…
Differential cystine and dibasic amino acid handling after loss of function of the amino acid transporter b0,+ AT (Slc7a9) in mice
2013
Cystinuria is an autosomal recessive disease caused by mutations in SLC3A1 ( rBAT) and SLC7A9 ( b 0,+ AT). Gene targeting of the catalytic subunit ( Slc7a9) in mice leads to excessive excretion of cystine, lysine, arginine, and ornithine. Here, we studied this non-type I cystinuria mouse model using gene expression analysis, Western blotting, clearance, and brush-border membrane vesicle (BBMV) uptake experiments to further characterize the renal and intestinal consequences of losing Slc7a9 function. The electrogenic and BBMV flux studies in the intestine suggested that arginine and ornithine are transported via other routes apart from system b0,+. No remarkable gene expression changes were…
Antidepressant-like activity of hyperforin and changes in BDNF and zinc levels in mice exposed to chronic unpredictable mild stress.
2019
Abstract Chronic unpredictable mild stress (CUMS) - a rodent model of depression mimics a variety of neurochemical and behavioral alterations similar to those seen in human depression. This study evaluated the antidepressant activity of hyperforin in the CUMS model using fluoxetine (FLX) as a reference drug. The antidepressant-like effects of hyperforin and FLX were evaluated in the tail suspension test (TST), forced swim test (FST), and splash test (SPT). CUMS induced an increase in immobility time in mice (pro-depressive effects) in the FST and TST. CUMS-induced changes were reversed by chronic treatment with hyperforin (2.5 and 5 mg/kg), as well as FLX (10 mg/kg). SPT results revealed a …
Muscle protein synthesis, mTORC1/MAPK/Hippo signaling, and capillary density are altered by blocking of myostatin and activins
2012
Loss of muscle mass and function occurs in various diseases. Myostatin blocking can attenuate muscle loss, but downstream signaling is not well known. Therefore, to elucidate associated signaling pathways, we used the soluble activin receptor IIb (sActRIIB-Fc) to block myostatin and activins in mice. Within 2 wk, the treatment rapidly increased muscle size as expected but decreased capillary density per area. sActRIIB-Fc increased muscle protein synthesis 1–2 days after the treatment correlating with enhanced mTORC1 signaling (phosphorylated rpS6 and S6K1, r = 0.8). Concurrently, increased REDD1 and eIF2Bε protein contents and phosphorylation of 4E-BP1 and AMPK was observed. In contrast, pr…
Paracrine Activation of Hepatic CB1 Receptors by Stellate Cell-Derived Endocannabinoids Mediates Alcoholic Fatty Liver
2008
SummaryAlcohol-induced fatty liver, a major cause of morbidity, has been attributed to enhanced hepatic lipogenesis and decreased fat clearance of unknown mechanism. Here we report that the steatosis induced in mice by a low-fat, liquid ethanol diet is attenuated by concurrent blockade of cannabinoid CB1 receptors. Global or hepatocyte-specific CB1 knockout mice are resistant to ethanol-induced steatosis and increases in lipogenic gene expression and have increased carnitine palmitoyltransferase 1 activity, which, unlike in controls, is not reduced by ethanol treatment. Ethanol feeding increases the hepatic expression of CB1 receptors and upregulates the endocannabinoid 2-arachidonoylglycer…
Expression of Na+-d-glucose cotransporter SGLT2 in rodents is kidney-specific and exhibits sex and species differences
2012
With a novel antibody against the rat Na+-d-glucose cotransporter SGLT2 (rSGLT2-Ab), which does not cross-react with rSGLT1 or rSGLT3, the ∼75-kDa rSGLT2 protein was localized to the brush-border membrane (BBM) of the renal proximal tubule S1 and S2 segments (S1 > S2) with female-dominant expression in adult rats, whereas rSglt2 mRNA expression was similar in both sexes. Castration of adult males increased the abundance of rSGLT2 protein; this increase was further enhanced by estradiol and prevented by testosterone treatment. In the renal BBM vesicles, the rSGLT1-independent uptake of [14C]-α-methyl-d-glucopyranoside was similar in females and males, suggesting functional contribution of…
Myogenic NOS and endogenous NO production are defective in colon from dystrophic (mdx) mice.
2001
The aim of the present study was to evaluate whether alterations in the distribution and/or function of nitric oxide synthase (NOS) could be involved in the development of the spontaneous mechanical tone observed in colon from dystrophic ( mdx) mice. By recording the intraluminal pressure of isolated colon from normal mice, we showed that Nω-nitro- l-arginine methyl ester (l-NAME) increased the tone, even in the presence of tetrodotoxin. The effect was prevented by l-arginine, nifedipine, or Ca2+-free solution. In colon from mdx mice, l-NAME was ineffective. Immunohistochemistry revealed that the presence and distribution of neuronal (nNOS), endothelial, and inducible NOS isoforms in smooth…