Calyculin a Modulates Voltage-Dependent Outward Current in Guinea-Pig Taenia Coli Smooth Muscle Cells
Protein kinases modulate the electrical activity of various cells through their action on membrane ion channels. In cardiac and smooth muscle cells, enhancement of a number of K+ currents by β-adrenergic agonists, such as isoproterenol (ISP), may result from a direct phosphorylation of K+ channel protein by cAMP-dependent protein kinase (A kinase) (Kolb, 1990). On the other hand, calyculin A (CL-A) which is a toxin isolated from marine sponge (Discodermia calyx) has a potent inhibitory action on protein phosphatase activities (Ishihara et al., 1989).
KeywordsOkadaic Acid Outward Current Marine Sponge Potent Inhibitory Action Protein Phosphatase Activity
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