Blocking effect of puerarin on beta-adrenoceptor of isolated organs and whole animal
Abstract
Puerarin 0.1 and 3 micromol/L caused parallel rightward shifts of isoproterenol concentration-response curves for positive chronotropic action on isolated right atria of rabbits and negative inotropic action on isolated trachea ofguinea pigs. The pA2 values and slopes of isoproterenol antagonist effect were 7.79 and 5.33, respectively.
Puerarin 20-100 mg/kg iv blocked the isoproterenol-induced tachycardia and hypotension in cats, decreased normal heart rate and reduced the blood pressure in anesthetized cats. All these effects were attenuated or reversed by the prior reserpinisation. Puerarin also reduced significantly or blocked completely the secondary vasodilating hypotensive response of epinephrine 10 microg/kg iv and the isoproterenol-induced shortening of P-R and Q-T intervals.
Keywords:
Puerarin 20-100 mg/kg iv blocked the isoproterenol-induced tachycardia and hypotension in cats, decreased normal heart rate and reduced the blood pressure in anesthetized cats. All these effects were attenuated or reversed by the prior reserpinisation. Puerarin also reduced significantly or blocked completely the secondary vasodilating hypotensive response of epinephrine 10 microg/kg iv and the isoproterenol-induced shortening of P-R and Q-T intervals.