Effects of m-nifedipine on dihydropyridine binding sites in cardiac and cerebral cortex cell membranes from left ventricular hypertrophied rats.
m-Nifedipine (m-Nif 20 mg.kg-1.d-1 ig for 9 wk) decreased left ventricular weight in the renovascular hypertensive rats (P < 0.01). Though not significantly affecting the density of dihydropyridines (DHP) receptor (Bmax), m-Nif administered whether for prevention (6 wk postclipping) or for regression (9 wk postclipping), markedly decreased the total number of DHP binding sites in hypertrophied left ventricle (LV). m-Nif also reduced the dissociation constant (Kd) of DHP binding sites in the membranes of LV and cerebral cortex from cardiac hypertrophied rats (P < 0.01). These effects of m-Nif were similar to those of nifedipine (Nif) in the same dosage. The results suggest that m-Nif can prevent and regress the LV hypertrophy resulted from renovascular hypertension and reduce the total number of DHP binding sites in the membranes of LV from cardiac hypertrophied rats.
Xi
T
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Department of Cardiovascular Pharmacology, Nanjing Medical College, China.
Rao
M R
MR
D000818:Animals; D001665:Binding Sites; D020746:Calcium Channels, L-Type; D002540:Cerebral Cortex / Q000378:metabolism*; D004095:Dihydropyridines / Q000378:metabolism*; D006978:Hypertension, Renovascular / Q000378:metabolism; D017379:Hypertrophy, Left Ventricular / Q000378:metabolism* / Q000517:prevention & control; D007536:Isomerism; D008297:Male; D009124:Muscle Proteins / Q000378:metabolism*; D009543:Nifedipine / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley
D020746:Calcium Channels, L-Type; D004095:Dihydropyridines; D009124:Muscle Proteins; D009543:Nifedipine