8-Bromoguanosine 3':5'-cyclic monophosphate decreases intracellular free calcium concentrations in cultured vascular smooth muscle cells from rat aorta.
The effects of 8-bromoguanosine 3':5'-cyclic monophosphate (8-Br cGMP) on intracellular free calcium concentrations ([Ca2+]i) in cultured rat aortic vascular smooth muscle cells (VSMCs) loaded with fura-2 were recorded microfluorometrically. Irrespective of whether VSMCs were at rest (in 5 mM K+ PSS), under Ca2+ depletion (in Ca2+-free medium for 10 min) and K+ depolarization (in high K+ PSS), [Ca2+]i was actively reduced and reached a new and lower steady-state level with the application of 8-Br cGMP. This may be the first and direct evidence that cGMP, a putative mediator of various vasodilators, actively reduces [Ca2+]i in VSMCs.
D000818:Animals; D001011:Aorta / Q000032:analysis; D002118:Calcium / Q000032:analysis*; D000252:Calcium-Transporting ATPases / Q000032:analysis; D002478:Cells, Cultured; D006152:Cyclic GMP / Q000031:analogs & derivatives* / Q000494:pharmacology; D009131:Muscle, Smooth, Vascular / Q000032:analysis* / Q000187:drug effects; D051381:Rats
C016276:8-bromocyclic GMP; D000252:Calcium-Transporting ATPases; D006152:Cyclic GMP; D002118:Calcium