title: Effects of cigarette smoke on rat lung and liver ornithine decarboxylase and aryl hydrocarbon hydroxylase activities and lung benzo(a)pyrene metabolism.
abstract: The response of rat lung and liver ornithine decarboxylase (ODC) and aryl hydrocarbon hydroxylase (AHH) activities and lung benzo(a)pyrene (BP) metabolism was studied after exposing the rats to cigarette smoke. A close analysis of the time curves for ODC and AHH activities in rat lung and liver after a single exposure to cigarette smoke resulted in no clear correlation between the two parameters. Prolonged treatment (10 days) produced an increase in pulmonary ODC activity; hepatic ODC activity was unaffected. 10-day treatment was ineffective in raising AHH activity above values observed after a single treatment. BP metabolism, as determined in isolated perfused lungs by the appearance of organic- and water-soluble metabolites in the perfusion medium, the amount of covalently bound metabolites in lung tissue and the disappearance of unchanged 3-H BP from the perfusate, was markedly increased in response to cigarette smoke treatment. The data presented indicate that induction of AHH activity and increased metabolism of BP do not necessarily require a pre-existing increase in ODC activity.
mesh_terms: D000818:Animals; D001189:Aryl Hydrocarbon Hydroxylases / Q000378:metabolism*; D001564:Benzo(a)pyrene; D001580:Benzopyrenes / Q000378:metabolism*; D002262:Carboxy-Lyases / Q000378:metabolism*; D004781:Environmental Exposure; D008099:Liver / Q000201:enzymology*; D008168:Lung / Q000378:metabolism*; D008297:Male; D009955:Ornithine Decarboxylase / Q000378:metabolism*; D010947:Plants, Toxic; D051381:Rats; D011919:Rats, Inbred Strains; D012906:Smoke / Q000009:adverse effects*; D014026:Nicotiana; D014316:Tritium
chemical_list: D001580:Benzopyrenes; D012906:Smoke; D014316:Tritium; D001564:Benzo(a)pyrene; D001189:Aryl Hydrocarbon Hydroxylases; D002262:Carboxy-Lyases; D009955:Ornithine Decarboxylase