The chromogranin A- derived N-terminal peptide vasostatin-I: In vivo effects on cardiovascular variables in the rabbit

► VS-1 administered i.v. to awake and anesthetized rabbits produces vasoconstrictor and vasodilator effects. ► The catecholamine-mediated vasoconstrictor effect predominates in the first 2 h. ► A longer-lasting vasodilator effect is unmasked by α-adrenergic blockade. ► VS-1 appears to stimulate the release of catecholamines at peripheral level. ► The vasodilatory effect, non adrenergic in origin, is consistent with previous reports based on in vitro models.