Imms F J, Neame R L, Powis D A
Br J Pharmacol. 1979 Nov;67(3):367-70. doi: 10.1111/j.1476-5381.1979.tb08689.x.
1 The antagonism by the beta-adrenoceptor blocking drugs, propranolol (non-selective) and practolol (beta-selective), of the cardiovascular actions of isoprenaline has been investigated in the rat. 2 All doses of practolol (0.1, 1 and 3 mg/kg) blocked the cardio-accelerator action of isoprenaline but only the largest dose blocked the vasodilator effect. 3 All doses of propranolol (0.01, 0.03 and 0.1 mg/kg) blocked the vasodilator effect of isoprenaline but only the largest dose diminished the tachycardia. 4 It is concluded that in the rat, as in other species, beta-adrenoceptors may be subdivided into beta 1 (cardiac) and beta 2 (peripheral vascular) types.