Central and peripheral hypotensive effects of the optical isomers of nicardipine, a dihydropyridine calcium channel antagonist, in rats.

Central and peripheral hypotensive effects of (+)- and (-)-nicardipine (1-10 micrograms/kg i.v. or i.c.v.) were investigated in normotensive and SH rats. The results suggest that a stereoselectivity exists for the peripheral and central hypotensive effects of the nicardipine isomers. (+)-Nicardipine was shown to be 3-8 times as potent as the (-) isomer in reducing blood pressure in all the experiments.