YC-1-like potentiation of nitric oxide-dependent activation of soluble guanylate cyclase by adrenochrom

Abstract

The influence of adrenochrome and YC-1 on spermine NONO-induced activation of human soluble guanylyl cyclase was investigated. Adrenochrome (0.1-10 microM) had no effect on the basal activity, but it potentiated in concentration-dependent manner the spermine NONO-induced activation of this enzyme. Adrenochrome, like YC-1, sensitized guanylyl cyclase towards nitric oxide (NO) and produced the leftward shift of spermine NONO concentration responce curve. Addition of adrenochrome decreased the YC-1-induced leftward shift of spermine NONO concentration response curve. Adrenochrome also inhibited (by 63%) the enzyme activation by YC-1. These data demonstrates the possible competition between adrenochrome and YC-1. Thus, synergistic activation of NO-stimulated guanylyl cyclase activity by adrenochrome represents a new biochemical effect of this compound and indicates that adrenochrome may act as an endogenous regulator of NO-dependent stimulation of soluble guanylyl cyclase. This new property of adrenochrome, similar to YC-1, is necessary taking into account, especially under conditions of overproduction of adrenochrome in organism.