Novel Ca2+ signalling mechanisms in vascular myocytes: symposium overview.

This commentary presents the proceedings of the symposium sponsored by Cardiovascular Section of American Physiological Society in San Diego, CA on 12 April 2003. The major focus of this symposium was on the actions and physiological relevance of several novel Ca2+ signalling mechanisms in vascular smooth muscle (VSM) cells. Five important topics were presented in this symposium including the discovery and roles of cyclic ADP-ribose (cADPR) and nicotinic acid adenine dinucleotide phosphate (NAADP) in mediating Ca2+ release, Ca2+ sparks and activation of plasma membrane KCa channels in VSM cells, the role of cADPR-mediated activation of ryanodine receptors in the control of vascular tone, the role of [Ca2+]i in mechanotransduction in the arterioles, and interactions of mitochondrial Ca2+ release and SR Ca2+ mobilization. The purpose of this symposium was to promote discussions and exchange of ideas between scientists with interests in Ca2+ signalling mechanisms and those with interests in vascular physiology and pharmacology. The cross-fertilization of ideas is expected to greatly advance our understanding of the physiological and pharmacological relevance of these new Ca2+ signalling mechanisms.