Effects of m-nifedipine and nifedipine given intraduodenally on coronary flow, myocardial oxygen, and carbon dioxide metabolism in dogs
Rao, M.R.; Liu, Q.Y.; Jia, S.L.
Zhongguo Yao Li Xue Bao 14(Suppl): S25-S27
1993
ISSN/ISBN: 0253-9756 PMID: 8010068 Document Number: 414641
In anesthetized dogs intraduodenal administration of m-nifedipine (m-Nif) 0.4 mg cntdot kg-1, coronary flow increased from 708+- 72 to 880+-150 ml cntdot min-1 cntdot kg-1 (+24%) at 5 min, to 1976+-350 ml cntdot min-1 cntdot kg-1 (+179%) at 30 min, and to 998+-250 ml cntdot min-1 cntdot kg-1 (+ 41%) at 4 h. At the dose of nifedipine (Nif), coronary flow increased from 778 +-91 to 1080+-90 ml cntdot min-1 cntdot kg-1 (+39%) at 3 min and to 1836+-280 ml cntdot min-1 cntdot kg-1 (+136%) at 90 min. m-Nif was more 43% potent than Nif and the duration of action of m-Nif was longer. m-Nif reduced heart rate by -39%, while Nif reduced only 11%. m-Nif increased coronary sinus O-2 content and reduced MVO-2, and no difference was seen between these 2 drugs. However, the rate of CO-2 production with m-Nif was reduced to a greater degree than that of Nif. The results indicated that m-Nif was more beneficial in alleviating myocardial ischemia than that of Nif.