Ciliary beat frequency of hamster oviducts is decreased in vitro by exposure to solutions of mainstream and sidestream cigarette smoke

Epidemiological data support a correlation between smoking and increased incidence of ectopic pregnancy, yet the causal mechanism responsible for this relationship is unknown. The purpose of this study was to examine the effect of solutions containing dissolved mainstream (MS) or sidestream (SS) cigarette smoke on ciliary beat frequencies (CBF) in explants of hamster oviducts. MS smoke is the puff inhaled by an active smoker, while SS smoke leaves the burning end of cigarette. SS smoke is inhaled by both active and passive smokers. Experiments were performed in handmade perfusion chambers using infundibula from hamster oviducts. After a short incubation in Earle's balanced salt solution containing HEPES buffer (EBSS-H), chambers were flushed with one of six types of smoke solution prepared in EBSS-H, and incubation continued 19 min. A second perfusion (washout) was then done using EBSS-H alone to determine whether effects induced by the smoke solutions could be reversed. CBF were determined at three times in both the smoke and washout solutions, and means were compared to values obtained in the initial EBSS-H incubation. All smoke solutions except the SS particulate solution inhibited CBF in a dose-dependent manner. Whole MS and whole SS smoke solution at the highest strength tested caused the greatest inhibition and in some cases completely stopped ciliary beating. Both single-strength and 0.1-strength MS gas phase solutions, which contained concentrations of nicotine in the range found in typical human smokers, produced about 50% inhibition of ciliary beating. Inhibition was generally seen within 2-12 min of adding smoke solutions.