Search results for "MICE"
showing 10 items of 6027 documents
Agouti-related peptide-expressing neurons are mandatory for feeding.
2005
Multiple hormones controlling energy homeostasis regulate the expression of neuropeptide Y (NPY) and agouti-related peptide (AgRP) in the arcuate nucleus of the hypothalamus. Nevertheless, inactivation of the genes encoding NPY and/or AgRP has no impact on food intake in mice. Here we demonstrate that induced selective ablation of AgRP-expressing neurons in adult mice results in acute reduction of feeding, demonstrating direct evidence for a critical role of these neurons in the regulation of energy homeostasis.
Midregion parathyroid hormone-related protein inhibits growth and invasion in vitro and tumorigenesis in vivo of human breast cancer cells.
2001
Parathyroid hormone-related protein (PTHrP) is critical for normal mammary development and is overexpressed by breast cancers. PTHrP is a peptide hormone that undergoes extensive post-translational processing, and PTHrP(38–94)-amide is one of the mature secretory forms of the peptide. In this study, we explored the effect of PTHrP(38–94)-amide in a panel of six breast cancer cell lines “in vitro” and in MDA-MB231 cells “in vivo” specifically examining cell viability, proliferation, invasiveness, and growth in nude mice. PTHrP(38–94)-amide markedly inhibited proliferation and also caused striking toxicity and accelerated cell death in breast cancer cells. In addition, direct injection of PTH…
Nitric oxide triggers mammary gland involution after weaning: remodelling is delayed but not impaired in mice lacking inducible nitric oxide synthase
2010
During mammary gland involution, different signals are required for apoptosis and tissue remodelling. To explore the role of NO in the involution of mammary tissue after lactation, NOS2 (inducible nitric oxide synthase)-KO (knockout) mice were used. No apparent differences were observed between NOS2-KO and WT (wild-type) animals during pregnancy and lactation. However, upon cessation of lactation, a notable delay in involution was observed, compared with WT mice. NOS2-KO mice showed increased phosphorylation of STAT (signal transducer and activator of transcription) 5 during weaning, concomitant with increased beta-casein mRNA levels when compared with weaned WT glands, both hallmarks of th…
Motor activity in group-housed and isolated mice with short and long attack latencies: Effects of scopolamine
2002
Isolation-induced behavioral changes are well described in mice, although few studies have investigated the involvement of the cholinergic system in these effects. It has also been suggested that mice that display short or long attack latencies show differences in their reactions to a novel environment. The purpose of the present study was, first, to investigate locomotor activity in grouped and isolated mice that displayed short or long attack latencies and, second, to evaluate locomotor activity to determine whether it was affected interactively by differential housing and scopolamine treatment. Two experiments were performed in which NMRI mice, either isolated or group housed, were used …
Herpes simplex virus type 1 and 2 in the adrenal glands: Replication and histopathology
1986
The adrenal glands were shown to be the most severely infected organs in the early phase of HSV-1 infections (up to 10 days p.i.) after i.p. infections in mice. Virus could be isolated from the adrenal glands as early as one hour after infection with pathogenic and apathogenic strains. Infection of the adrenal glands is a result of viremia. The content of HSV-1 (5 strains) was much higher in the adrenals than in spleen and liver. It peaked at 3-4 days p.i. compared to 1-2 days in spleen and liver. Only strain 17 syn+ produced low tissue titres in the adrenal glands. Morphologic alterations by HSV-1 infections commenced with distinct foci 2 days after infection in the zona fasciculata, detec…
Embryonic adhesion is not affected by endometrial leptin receptor gene silencing.
2006
Objective In rodents, evidence suggests that the leptin system is mandatory for embryonic implantation. We aimed to investigate the functional relevance of the endometrial leptin receptor (OB-R) in the adhesion phase of human implantation. Design We used an in vitro model for embryonic adhesion, composed of a human endometrial cell line (HEC1-A) and B6C3F1 mouse embryos. The OB-R gene was silenced in a stable manner by RNA interference, and embryonic adhesion rates were analyzed. Setting Research laboratory at a university-affiliated center. Intervention(s) RNA interference. Main Outcome Measure(s) Embryonic adhesion in cells treated with OB-R RNAi. Result(s) The OB-R shRNA-transfected cell…
Skin response to a carcinogen involves the xenobiotic receptor pregnane X receptor.
2015
Skin is in daily contact with potentially harmful molecules from the environment such as cigarette smoke, automobile emissions, industrial soot and groundwater. Pregnane X receptor (PXR) is a transcription factor expressed in liver and intestine that is activated by xenobiotic chemicals including drugs and environmental pollutants. Topical application of the tumor initiator 7,12-dimethylbenz(a)anthracene (DMBA) enhances Pxr, Cyp1a1, Cyp1b1 and Cyp3a11, but not Ahr expression in the skin. Surprisingly, DMBA-induced Pxr upregulation is largely impaired in Langerin(+) cell-depleted skin, suggesting that DMBA mainly triggers Pxr in Langerin(+) cells. Furthermore, PXR deficiency protects from DN…
Repression of Cyclic Adenosine Monophosphate Upregulation Disarms and Expands Human Regulatory T Cells
2011
Abstract The main molecular mechanism of human regulatory T cell (Treg)-mediated suppression has not been elucidated. We show in this study that cAMP represents a key regulator of human Treg function. Repression of cAMP production by inhibition of adenylate cyclase activity or augmentation of cAMP degradation through ectopic expression of a cAMP-degrading phosphodiesterase greatly reduces the suppressive activity of human Treg in vitro and in a humanized mouse model in vivo. Notably, cAMP repression additionally abrogates the anergic state of human Treg, accompanied by nuclear translocation of NFATc1 and induction of its short isoform NFATc1/αA. Treg expanded under cAMP repression, however,…
Effects of sodium fluoride on the mechanical activity in mouse gastric preparations.
2005
The aim of the present study was to investigate the responses induced by sodium fluoride (NaF) on gastric mechanical activity, using mouse whole-stomach preparations. The mechanical activity was recorded in vitro as changes of intraluminal pressure. In most of the preparations, NaF induced a tetrodotoxin-insensitive biphasic effect characterized by early relaxation followed by slowly developing contractile response. The contraction was dependent on the concentration of NaF, whereas the relaxation was observed at only 10–30 mmol/L NaF. The contractile effect was significantly reduced by nifedipine (an L-type Ca2+channel blocker), ryanodine or ruthenium red (inhibitors of Ca2+release from sar…
Biopterin metabolism and eNOS expression during hypoxic pulmonary hypertension in mice.
2013
International audience; Tetrahydrobiopterin (BH$_4$), which fosters the formation of and stabilizes endothelial NO synthase (eNOS) as an active dimer, tightly regulates eNOS coupling / uncoupling. Moreover, studies conducted in genetically-modified models demonstrate that BH$_4$ pulmonary deficiency is a key determinant in the pathogenesis of pulmonary hypertension. The present study thus investigates biopterin metabolism and eNOS expression, as well as the effect of sepiapterin (a precursor of BH$_4$) and eNOS gene deletion, in a mice model of hypoxic pulmonary hypertension. In lungs, chronic hypoxia increased BH$_4$ levels and eNOS expression, without modifying dihydrobiopterin (BH$_2$, t…