NMDAR-mediated activation of pannexin1 channels contributes to the detonator properties of hippocampal mossy fiber synapses.

Pannexins are large-pore ion channels expressed throughout the mammalian brain that participate in various neuropathologies; however, their physiological roles remain obscure. Here, we report that pannexin1 channels (Panx1) can be synaptically activated under physiological recording conditions in rodent acute hippocampal slices. Specifically, NMDA receptor (NMDAR)-mediated responses at the mossy fiber to CA3 pyramidal cell synapse were followed by a slow postsynaptic inward current that could activate CA3 pyramidal cells but was absent in Panx1 knockout mice.

Capsaicin Causes Vasorelaxation of Rat Aorta through Blocking of L-type Ca Channels and Activation of CB Receptors.

The aim of this work was to determine whether Capsaicin may exert a vascular regulation through the activation of CB and/or CB receptors causing vasorelaxation in the rat aorta. Our results show the location of TRPV1 mainly in the endothelial and smooth muscle cells membrane. Nevertheless, Capsaicin caused vasorelaxation of this artery through a mechanism independent of TRPV1, since the specific antagonists Capsazepine and SB-366791 did not block the effect of Capsaicin.

ACPA and JWH-133 modulate the vascular tone of superior mesenteric arteries through cannabinoid receptors, BK channels, and nitric oxide dependent mechanisms.

Background: Some cannabinoids, a family of compounds derived from Cannabis sativa (marijuana), have previously shown vasodilator effects in several studies, a feature that makes them suitable for the generation of a potential treatment for hypertension. The mechanism underlying this vasodilator effect in arteries is still controversial. In this report, we explored how the synthetic cannabinoids ACPA (CB-selective agonist) and JWH-133 (CB-selective agonist) regulate the vascular tone of rat superior mesenteric arteries.