Function of the hypothalamo-neurohypophysial system in rats with myocardial infarction is modified by melatonin

(i) CAL-induced myocardial infarction is the reason for increased hypothalamo-neurohypophysial system activity in rats; melatonin plays the role of inhibitory neuromodulator of vasopressin and oxytocin release in this state. (ii) Myocardial infarction evoked in pinealectomized rats is characterized by the inversion of the neurohumoral response pattern in respect of inhibited vasopressin release. (iii) Melatonin stimulates vasopressin (but decreases oxytocin) release in pinealectomized rats with myocardial infarction.