title: T-type Ca²⁺ channels in cerebral arteries: approaches, hypotheses, and speculation.
abstract: Cerebral blood flow is controlled by a network of resistance arteries that dilate and constrict to mechanical and chemical stimuli. Vasoactive stimuli influence arterial diameter through alterations in resting membrane potential and the influx of Ca²⁺ through voltage-gated Ca²⁺ channels. Historically, L-type Ca²⁺ channels were thought to be solely expressed in cerebral arterial smooth muscle. Recent studies have, however, challenged this perspective, by providing evidence of T-type Ca²⁺ channels in vascular tissues. This perspective piece will introduce T-type Ca²⁺ channels, their electrophysiological properties, and potential roles in arterial tone development. We begin with a brief overview of Ca²⁺ channels and a discussion of the approaches used to isolate this elusive conductance. We will then speculate on how the two T-type Ca²⁺ channels expressed in cerebral arterial smooth muscle might differentially influence arterial tone. This discovery of T-type Ca²⁺ channels alters our traditional understanding of Ca²⁺ dynamics in vascular tissue and fosters new avenues of research and insight into the basis of arterial tone development.
authors: Department of Physiology & Pharmacology, Hotchkiss Brain and Libin Cardiovascular Research Institutes, University of Calgary, Calgary, AB, Canada.
authors: Osama F
authors: OF
authors: Harraz
authors: Donald G
authors: DG
authors: Welsh
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism*; D020747:Calcium Channels, T-Type / Q000378:metabolism*; D002536:Cerebral Arteries / Q000378:metabolism*; D002560:Cerebrovascular Circulation / Q000502:physiology; D006801:Humans; D008955:Models, Cardiovascular; D009124:Muscle Proteins / Q000378:metabolism*; D009131:Muscle, Smooth, Vascular / Q000378:metabolism*
chemical_list: D020747:Calcium Channels, T-Type; D009124:Muscle Proteins; D002118:Calcium