Studies on epinephrine-induced lung edema in the rat. II. Hemodynamic changes.

In order to elucidate the pathogenesis of epinephrine (E)-induced lung edema (LE) as well as the mechanism of protection afforded by alpha-adrenoceptor blockade in urethane-anesthetized and bivagotomized rats, we investigated the influence of phentolamine (Phe) and prazosin (Praz) on arterial hypertension and LE provoked by continuous intravenous infusion of E and on blood pressure changes in left (LHV) and right (RHV) heart ventricles caused by a bolus injection of E at a LE-producing dose (1800 nmol/kg). Our results show that neither LE nor death are related to E-induced hypertension and also that LE-induction is accompanied by significant increases in LHV (telediastolic and systolic) as well as in RHV (systolic) pressures, of which the LHV telediastolic and the RHV systolic pressure increases are prevented by Phe and Praz at a dose capable of counteracting E-induced LE. The significance of this finding is briefly discussed.