Acute cocaine results in rapid rises in intracellular free calcium concentration in canine cerebral vascular smooth muscle cells: possible relation to etiology of stroke.
Effects of cocaine on intracellular free calcium concentration ([Ca2+]i) in cultured canine cerebral vascular smooth muscle cells were studied using digital imaging microscopy and the calcium molecular fluorescent indicator, fura-2. Acute treatment of cerebral vascular smooth muscle cells with cocaine HCl, from a low concentration of 10(-9) M up to 10(-5) M, induced significant increases of [Ca2+]i. Irrespective of the changes in [Ca2+]i, the subcellular distribution of [Ca2+]i appeared heterogeneous in both normal and cocaine-treated cells. These results suggest that cocaine induces cerebral vasospasm by a rapid elevation of [Ca2+]i in vascular smooth muscle cells; these ionic events could play a crucial role in the pathogenesis of cocaine-induced cerebral ischemia and stroke.
Zhang
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A
Department of Physiology, State University of New York, Health Science Center at Brooklyn 11203, USA.
Cheng
T P
TP
Altura
B T
BT
Altura
B M
BM
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002560:Cerebrovascular Circulation / Q000187:drug effects*; D002561:Cerebrovascular Disorders / Q000209:etiology; D003042:Cocaine / Q000494:pharmacology*; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000187:drug effects*
D003042:Cocaine; D002118:Calcium