Bradykinin inhibits a potassium M-like current in rat pheochromocytoma PC12 cells.
We studied the action of bradykinin (BK) on ionic currents in fused pheochromocytoma PC12 cells under voltage-clamp in whole-cell mode, and on intracellular calcium using fura-2 BK induced the development of an outward current associated with an increase in intracellular calcium, followed by inhibition of an M-like current. The outward current was blocked by (+)-tubocurarine, and prevented when the calcium BAPTA or high concentrations of inositol 1,4,5-triphosphate were introduced into the cell, whereas the M-like current and its inhibition by BK remained unaffected. The protein kinase activator phorbol 12,13 dibutyrate partially reduced the M-current. M-current density did not substantially change after prolonged treatment with nerve growth factor.
Villarroel
A
A
Howard Hughes Medical Institute, Department of Neurobiology and Behavior, SUNY, Stony Brook 11794-5230.
Marrion
N V
NV
Lopez
H
H
Adams
P R
PR
D000818:Animals; D001572:Benzofurans; D001920:Bradykinin / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism; D004553:Electric Conductivity / Q000187:drug effects; D005456:Fluorescent Dyes; D016257:Fura-2; D007425:Intracellular Membranes / Q000378:metabolism; D008564:Membrane Potentials; D009116:Muscarine / Q000494:pharmacology; D010673:Pheochromocytoma / Q000378:metabolism*; D015221:Potassium Channels / Q000187:drug effects / Q000378:metabolism*; D011493:Protein Kinase C / Q000378:metabolism; D051381:Rats; D014407:Tumor Cells, Cultured / Q000187:drug effects
D001572:Benzofurans; D005456:Fluorescent Dyes; D015221:Potassium Channels; D009116:Muscarine; D011493:Protein Kinase C; D001920:Bradykinin; D002118:Calcium; D016257:Fura-2