Inactivation of vasopressin by heart muscle.

The inactivation of vasopressin by heart as well as skeletal muscle was investigated in in vitro experiments. Heart muscle can inactivate vasopressin while skeletal muscle only binds some vasopressin. The mechanism of vasopres sin inactivation was studied by heat treatment, by determining pH optimum and by time-dependency studies. The inactivation of vasopressin by heart muscle proved to be an active process. The possible role of this phenomenon in coronary vasospasm and in coronary diseases is discussed.