Involvement of adenylate cyclase in mechanisms of denervation supersensitivity following surgical denervation of the dog heart.

Following surgical disruption (4-16 weeks) of the nerves supplying the dog heart, catecholamine (norepinephrine and epinephrine) levels in the atria and ventricles were markedly reduced. Using the 10,000 g particulate fraction as an enzyme source, the activation of adenylate cyclase by norepinephrine was considerably greater in the denervated myocardial preparations (atria and ventricles) than in control hearts. Moreover, in the denervated ventricular preparation fluoride (5 and 10mM) elicited a significantly greater stimulation of the enzyme than that observed in the controls.