Adhesion between the oocyte-cumulus complex and infundibulum plays an important, but poorly understood, role in oocyte pick-up. The purposes of this study were to determine which components of the oocyte-cumulus complex and oviductal epithelium function in adhesion, to measure adhesion under physiological conditions, and to examine the effect of modulation of adhesion on oocyte-cumulus complex pick-up rate. Oocyte-cumulus complexes containing an expanded matrix were readily transported into the oviduct, while unexpanded complexes lacking an extracellular matrix were not picked up, indicating that the matrix is necessary for pick-up. Transmission electron microscopy revealed that during pick-up, adhesion occurred specifically between the ciliary crowns of the oviduct and the granules and filaments of the cumulus matrix. An assay was developed using vacuum from a low-flow peristaltic precision pump, modified for bi-directional flow, to measure the strength of adhesion between the oocyte-cumulus complex and the oviductal epithelium, and adhesion was measured during physiological conditions. The lectin wheat germ agglutinin and the polycation poly-L-lysine were then used to modulate adhesion, and the effects of increasing or decreasing adhesion on oocyte pick-up rate and ciliary beat frequency were examined. The data show that 1) the matrix of the oocyte-cumulus complex and the ciliary crowns of the oviduct function in adhesion during pick-up and that adhesion is necessary for pick-up, 2) adhesion can be assayed quantitatively and is very uniform among control infundibula, and 3) decreasing or increasing adhesion decreases oocyte pick-up rate and in some cases prevents pick-up without affecting ciliary beat frequency.

Previous research has shown that oocyte cumulus complex (OCC) pickup rate is inhibited in hamsters when oviducts and OCCs are simultaneously exposed to cigarette smoke solutions, independent of any effect on ciliary beat frequency. The purpose of this research was to determine whether smoke solutions caused a change in adhesion between the OCC and infundibulum of the oviduct and to determine whether a change in adhesion could account for decreased OCC pickup rate. OCC pickup rate and adhesion were measured before and after infundibula or OCCs recovered from acute in vitro exposures to mainstream and sidestream whole, gas, or particulate smoke solutions. Ciliary beat frequency was also measured on infundibula. Overall, smoke solutions decreased oocyte pickup rate 40% to 80% below control levels and increased adhesion 52% to 91% above control levels when infundibula were pretreated. A change in adhesion was observed in cases for which decreased OCC pickup rate could not be explained by a change in ciliary beat frequency. OCC pickup rate decreased 20% to 35% below control levels and adhesion increased 39% to 54% above control levels when OCCs were pretreated. These data show not only that cigarette smoke causes an increase in OCC adhesion to the oviduct, but also that there is a correlation between increased adhesion and decreased OCC pickup rate. The results also show that the both the OCC and oviduct are targets of cigarette smoke. The oviduct is more sensitive to the adverse effects of smoke; however, this may be caused by a combined impact on mechanisms involved in both adhesion and ciliary function.