It is now clear that there exists a third category of memory cells that never returns to the circulation. These tissue-resident memory T (T-RM) cells are phenotypically distinct from T-EM cells, persist in elevated numbers in areas involved
in prior infection and have been implicated in various immune phenomena, such as the control of persisting infections and immune disorders in fixed regions of the body.”
“The aim of this study was to investigate the cellular mechanism involved in the potent vasodilatory action of PIGF on mesenteric resistance arteries from pregnant rats. PIGF (3 nM) induced a vasodilation of 64 +/- 3.8% that was completely abolished by endothelial denudation. Significant dilation (28 +/- 4.0%) remained, selleck products however, in the presence of nitric oxide synthase and cyclooxygenase inhibition, and was associated with significant reductions in vascular smooth muscle cell calcium. Absence of dilation in
potassium-depolarizing solution (30 Selleck BAY 1895344 mm) confirmed its dependence on endothelial-derived hyperpolarization factor. Subsequent studies established that vasodilation was abolished by pharmacologic inhibition of SK(Ca) (apamin) and BK(Ca) (iberiotoxin) but not IK(Ca) (tram-34) potassium channels. In summary, PIGF acts through the release of a combination of endothelium-derived relaxation factors. Based on the results of potassium channel blockade, we suggest that it induces endothelial hyperpolarization via SK(Ca) channel activation; this, in turn, leads to the release of a diffusible mediator that activates vascular smooth muscle selleck chemicals llc BK(Ca) channels, hyperpolarization and vasodilation. This is the first study to identify the mechanism for PIGF/VEGFR-1 resistance
artery dilation in the pregnant state, whose attenuation likely contributes to the systemic hypertension characteristic of preeclampsia. Copyright (C) 2011 S. Karger AG, Basel”
“Maternal separation is known to induce long-term changes in neuroendocrine and emotional responsiveness to stress in a large variety of models. We examined an animal model of early deprivation in Sprague-Dawley rats consisting of separating litters from their mothers and littermates 3 h daily during postnatal days 2 to 15. In adulthood, maternally deprived rats in comparison with non-deprived controls exhibited an increase in anxiety and depression-related behaviors in the open-field and forced swim tests. Because serotonin (5-HT) 5-HT1A receptors seem to play an important role in the pathophysiology of major depression and in the mechanism of action of antidepressants, we investigated if 5-HT1A receptor function is altered in deprived rats.