Identification of cigarette smoke components that alter functioning of hamster (Mesocricetus auratus) oviducts in vitro

Previous studies have shown that solutions of mainstream and sidestream cigarette smoke decrease both ciliary beat frequency and oocyte cumulus complex pick-up rate of hamster oviducts in vitro. The purpose of this study was to identify the component(s) in smoke that produces these effects. Chemicals reported to be ciliotoxic in other systems were tested on hamster infundibula at various concentrations to determine whether a dose-response inhibition of ciliary beat frequency occurred. In addition, the concentration of each test component was measured in mainstream and sidestream smoke solutions (whole, particulate, and gas phase). All test components (acrolein, formaldehyde, phenol, acetaldehyde, and potassium cyanide [KCN]) inhibited ciliary beat frequency in a dose-dependent manner. Inhibition of ciliary beat frequency was at least partially reversible for all test compounds except acrolein. The concentrations of acrolein, formaldehyde, and phenol that were required to inhibit beat frequency were at least 3-50 times higher than their corresponding concentrations in smoke solutions. In contrast, cyanide was present in all smoke solutions at concentrations sufficient to inhibit ciliary beat frequency. Cilia on the outer surface of the infundibulum function in picking up the oocyte cumulus complex. Oocyte cumulus complex pick-up rate was measured in vitro at KCN concentrations shown to inhibit ciliary beat frequency. Pick-up rate was likewise inhibited by KCN and remained significantly depressed after washout of KCN. These data show that cyanide is a potent inhibitor of both ciliary beat frequency and oocyte cumulus complex pick-up rate and that its concentration in smoke solutions is sufficiently high to explain the previously reported inhibition of these oviductal processes.