treatment of monolayers of chick embryo hepatocytes with the calcium channel blocking drugs nifedipine and verapamil resulted in a decrease in the activity of uroporphyrinogen decarboxylase , an increase in the activity of delta-aminolaevulinate synthase and accumulation of porphyrins with uroporphyrin and heptacarboxylic porphyrin predominating .
C0032712
porphyrins
C0042093
uroporphyrin