Tension Development, Myosin Light Chain Phosphorylation and Changes in Intracellular Free [Ca2+]i Induced by α1- and α2- Adrenoceptor Agonists
Part of the
Experimental Biology and Medicine
book series (EBAM, volume 26)
Vascular smooth muscle tone is regulated by a complex set of processes which vary with location of the vascular bed and the species being studied. Thus, in any synthesis of these regulatory processes, one must consider not only the effects of neurotransmitters but also vasoactive factors including hormones, locally produced substances (e.g., endothelium-derived factors) and changes in the local ionic milieu. Much emphasis has been placed on describing the effects of a specific vasoactive substance, or class of substances, on a particular vascular tissue. Much less emphasis, however, has been placed on understanding the cellular basis for the interactions (synergistic or otherwise) which occur between different vasoactive substances. To address this deficit, we are investigating the roles of α1- and α2- adrenoceptors in the regulation of vascular tone. The overall objective of this study was to determine not just the effects of individual agonists but to analyse the synergistic interactions that occur when vascular smooth muscle cells are exposed to sub-threshold concentrations of angiotensin II (ATII) prior to α-adrenergic agonists.
KeywordsTension Development Vasoactive Substance Adrenoceptor Agonist Myosin Light Chain Phosphorylation Myosin Phosphorylation
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