Protein Kinase C (PKC) Activation Lowers the Calcium Requirement for Cerebral Artery Myogenic Tone
The occurrence of myogenic tone in the cerebral circulation is well documented, and a number of earlier studies have characterized both the extent and pattern of arterial responses to altered transmural pressure (1–4). With the possible exception of the cat (4,5), the response of cerebral arteries to pressure or stretch appears to be truly myogenic in nature in most species examined (see 6 for review), although there are still several large gaps in our understanding of the underlying mechanisms. For example, neither the identity nor the location of the mechanosensor sensor is known, and the intracellular transduction mechanisms are only now beginning to be understood. Currently, the consensus is that the expression of myogenic tone involves a complementary interaction between transmembrane ionic fluxes and enzymatic activation.
KeywordsCerebral Artery Physiological Saline Solution Calcium Entry Lumen Diameter Transmural Pressure
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