contractile responses of shr femoral artery to bay k 8644 were antagonized competitively by nifedipine ( pa2 = 8.36 ) , a dihydropyridine ca++ antagonist , but noncompetitively by diltiazem , a non-dihydropyridine ca++ antagonist .
C0028066
nifedipine
C0012315
dihydropyridine