HYPOTENSIVE ACTION OF ISOPROPYLAMINE VANILLINATE / 中国药理学通报

ABSTRACT

I sopropylmine vanillinate (IV) given iv 5 , 10 mg/kg in anesthe tized rats produced a dose-dependent decrease in mean arterial pressure and a concomitant decrease in heart rate.In pithed rats IV was unable to shift the phenylephrine doserespon-se curve to the right, but prazosine caused 53-fold shift.No direct effect of vasodilation was shown by IV on rabbit aorta strips .The concentration-response curve of isoprenaline in isolated rat right atrium was competitively inhibited by IV and propranolol. pA2 value was 4.0 for IV and 8.2 for propranolol. In addition, 'IV depressed contractility & heart rate of isolated rat atria.These results suggest that the hypotensive action of IV may be related to the decrease of HR, inhibition of contractility and slight blocking of B-adrenergic receptor. However the mechanism underlying the hypotensive effect of IV is to be further studied.