Voltage-gated Ca2+channel activity modulates smooth muscle cell calcium waves in hamster cremaster arterioles

Smooth muscle alpha1D-adrenoceptors mediate phenylephrine-induced vasoconstriction and increases in endothelial cell Ca2+ in hamster cremaster arterioles.

BACKGROUND AND PURPOSE alpha(1)-Adrenoceptor agonists induce Ca(2+)-transients in endothelial cells (ECs) of arterioles. However, the presence of alpha(1)-adrenoceptors on arteriolar ECs has not been excluded, and the identity of alpha(1)-adrenoceptor subtypes in arterioles only has been inferred from pharmacology. Therefore, we determined which subtypes were expressed by vascular smooth muscle...

Elevation of intracellular calcium in smooth muscle causes endothelial cell generation of NO in arterioles.

It is well known that vascular smooth muscle tone can be modulated by signals arising in the endothelium (e.g., endothelium-derived relaxing factor, endothelium-derived hyperpolarizing factor, and prostaglandins). Here we show that during vasoconstriction a signal can originate in smooth muscle cells and act on the endothelium to cause synthesis of endothelium-derived relaxing factor. We studie...

Voltage-Gated Calcium Channels

Voltage-gated calcium channels.

Voltage-gated calcium (Ca(2+)) channels are key transducers of membrane potential changes into intracellular Ca(2+) transients that initiate many physiological events. There are ten members of the voltage-gated Ca(2+) channel family in mammals, and they serve distinct roles in cellular signal transduction. The Ca(V)1 subfamily initiates contraction, secretion, regulation of gene expression, int...

Bcl-2 decreases voltage-gated K+ channel activity and enhances survival in vascular smooth muscle cells.

Cell shrinkage is an incipient hallmark of apoptosis in a variety of cell types. The apoptotic volume decrease has been demonstrated to attribute, in part, to K+ efflux; blockade of plasmalemmal K+ channels inhibits the apoptotic volume decrease and attenuates apoptosis. Using combined approaches of gene transfection, single-cell PCR, patch clamp, and fluorescence microscopy, we examined whethe...