Pharmacokinetics of m-nifedipine in rabbits after intravenous injection.
OBJECTIVE
To study the dose effects on pharmacokinetics of m-Nif.


METHODS
Fifteen rabbits were divided into 3 groups receiving i.v. m-Nif 0.5, 1, and 2 mg.kg-1. Plasma levels of m-Nif were determined with HPLC method.


RESULTS
The concentration-time data were fitted with 2-compartment model. After i.v. 1 mg.kg-1, the parameters were: Vd = 0.37 +/- 0.10 L.kg-1, T1/2 alpha = 6.4 +/- 2.9 min, T1/2 beta = 84 +/- 22 min, AUC = 94 +/- 16 mg.min.L-1, Cl = 0.65 +/- 0.13 L.kg-1.h-1. No statistically significant difference was found in Cl and T1/2 beta between 3 dose groups. AUC (standardized to body weight) was correlated with doses.


CONCLUSIONS
m-Nif was distributed widely and eliminated at a fairly rapid rate in the rabbits. No dose-dependent pharmacokinetics was found after i.v. m-Nif 0.5-2 mg.kg-1. m-Nifedipine, 2, 6-dimethyl-3, 5-dicarbomethoxy-4-(3'-nitrophenyl)-1, 4-dihydropyridine (m-Nif) is a new calcium channel blocker. Dihydropyridine calcium channel antagonists are mainly used for the treatment of hypertension and angina[1]. Nifedipine is susceptible to photodegradation, but m-Nif is stable when exposed to light. The 2 drugs have the same antihypertensive effect[2]. So far, no report has been found on pharmacokinetics of m-Nif. Using a high performance liquid chromatographic (HPLC) method, we studied the dose effects on the pharmacokinetics of i.v. m-Nif 0.5, 1, and 2 mg.kg-1 in conscious rabbits.
Department of Pharmacy, General Hospital of Lanzhou Command of PLA, China.
J
J
Ma
J W
JW
Xie
Z P
ZP
Jia
L
L
Song
S Y
SY
Xu
D H
DH
Zhao
D000818:Animals; D019540:Area Under Curve; D002121:Calcium Channel Blockers / Q000008:administration & dosage / Q000493:pharmacokinetics*; D002851:Chromatography, High Pressure Liquid; D004305:Dose-Response Relationship, Drug; D007275:Injections, Intravenous; D008297:Male; D009543:Nifedipine / Q000008:administration & dosage / Q000493:pharmacokinetics*; D011817:Rabbits
D002121:Calcium Channel Blockers; D009543:Nifedipine