Subacute inhalation of cigarette smoke by pregnant and lactating rodents: AHH changes in perinatal tissues.

Abstract

To study the transplacental acquisition of tobacco smoke products and the effects on fetal tissue enzymes, pregnant rats, guinea pigs, and hamsters were exposed to freshly generated cigarette smoke via a nose-only inhalation system on a daily basis through the latter one-third (guinea pigs) or latter half (rats, hamsters) of the gestational period. Following euthanasia on the day of parturition, microsomal aryl hydrocarbon hydroxylase (AHH) activities were determined in the lungs, livers, and kidneys of both dams and fetuses. The possible acquisition of tobacco smoke products via the milk was studied by exposing lactating dams to cigarette smoke daily for either 4 or 14 days (rats), 4 or 7 days (guinea pigs), or 10 days (hamsters), with analysis of tissues from the euthanized pups for AHH. Pups were also exposed directly (nose only) to cigarette smoke. In the treated pregnant and lactating rat, maternal pulmonary, hepatic, and renal AHH was significantly increased but only fetal lung and the liver of 14-day-old pups showed a marked induction of AHH activity. In the pregnant and lactating guinea pig, only the pulmonary and renal AHH activities were increased following exposure, whereas in the fetuses and nursing pups, none of the tissue AHH activities was significantly altered by exposure. In the pregnant and lactating hamster, only the pulmonary AHH was increased following exposure to cigarette smoke, whereas the activity in fetal and pup tissues remained unchanged from the levels observed in control animals.(ABSTRACT TRUNCATED AT 250 WORDS)