Induction of pulmonary cytochrome P4501A1: interactive effects of nicotineand mecamylamine

The effect of the nicotinic receptor antagonist mecamylamine on nicotine-me diated convulsions and induction of pulmonary cytochrome P4501A1 (CYP1A1) w as examined in the rat. Mecamylamine blocked the convulsions and inhibited CYP1A1 induction by nicotine at the level of CYP1A1 activity (93%) and prot ein (97%), but independently induced the enzyme also at the level of activi ty and protein. The results show that mecamylamine antagonizes both the CYP 1A1 induction and convulsions by nicotine but, independently, is an inducer of the enzyme. The results indicate that CYP1A1 induction is not a consequ ence of the convulsant effects of nicotine. (C) 1999 Elsevier Science B.V. All rights reserved.