title: Venodilator effects of pranidipine, a 1,4-dihydropyridine Ca2+ channel antagonist, in rats: comparison with nifedipine and amlodipine.
abstract: The effects of pranidipine, a dihydropyridine Ca2+ channel antagonist, on mean circulatory filling pressure, an index of body venous tone, were compared with those of other dihydropyridines (nifedipine and amlodipine) and nitroglycerin in anaesthetized hexamethonium- and norepinephrine-treated rats. In this study, the compounds were used at doses having a equi-hypotensive effect. Intravenous bolus injection of pranidipine (10 and 30 microg/kg) significantly decreased mean circulatory filling pressure in a dose-dependent manner, as did nitroglycerin (30 and 100 microg/kg). Nifedipine (30 and 100 microg/kg), however, did not affect mean circulatory filling pressure. Amlodipine (1000 and 3000 microg/kg) decreased mean circulatory filling pressure only at the higher dose. These results suggest that pranidipine has a greater venodilator effect than nifedipine and amlodipine.
authors.affiliation: 2nd Tokushima Institute of New Drug Research, Otsuka Pharmaceutical Co., Ltd., Kawauchi-cho, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Hirano
authors.forename: M
authors.initials: M
authors.lastname: Ohura
authors.forename: K
authors.initials: K
authors.lastname: Orito
authors.forename: H
authors.initials: H
authors.lastname: Fujiki
authors.forename: G
authors.initials: G
authors.lastname: Miyakoda
authors.forename: T
authors.initials: T
authors.lastname: Mori
mesh_terms: D017311:Amlodipine / Q000494:pharmacology*; D000818:Animals; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D004095:Dihydropyridines / Q000494:pharmacology*; D007275:Injections, Intravenous; D008297:Male; D009543:Nifedipine / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D014690:Venous Pressure / Q000187:drug effects*
chemical_list: D002121:Calcium Channel Blockers; D004095:Dihydropyridines; D017311:Amlodipine; C038806:1,4-dihydropyridine; C048161:pranidipine; D009543:Nifedipine