Influence of Physical and Environmental Factors on Ion Channels in Arterial Muscle
Despite the existence of pharmacomechanical coupling in arterial muscle, it is now clear that electrophysiological events occurring at the plasma membrane, which regulate the resting membrane potential, largely influence the reactivity of intact arterial muscle cells. Factors which hyperpolarize arterial muscle inhibit voltage-operated Ca2+ channels reducing their ability to respond to stimuli. Similarly, factors which depolarize arterial muscle activate voltage-sensitive Ca2+ channels leading to activation. During the last ten years it has become apparent that one of the mechanisms responsible for the transduction of physical and environmental influences with respect to vascular reactivity is activation or inhibition of ion conductance systems setting a level of membrane potential around which vascular tone is enhanced or reduced.
KeywordsTransmural Pressure Arterial Muscle Myogenic Response Myogenic Tone Excise Membrane Patch
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