[The short-term and long-term effects of gamma-irradiation on the inotropic reaction of the myocardium during the activation of alpha- and beta-adrenoreceptors].

The contractile function of myocardium was impaired and its inotropic response to stimulation of alpha- and beta-adrenoreceptors decreased at early times (1-30 days) following whole-body gamma-irradiation with a dose of 1.0 Gy. Six months after irradiation the response of the isolated myocardium to stimulation of adrenoreceptors increased to exceed that of intact animals. In a year the reactivity of the myocardium towards alpha-adrenoreceptor agonists remained high and its sensitivity of phenylephrine hydrochloride increased considerably; the response to beta-adrenoreceptor agonists was virtually absent.