Assay and Importance of Adhesive Interaction Between Hamster (Mesocricetus auratus) Oocyte-Cumulus Complexes and the Oviductal Epithelium1

Abstract

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.

Expression of connexin 43 and gap junctional intercellular communication in the cumulus–oocyte complex in sheep

“…However, we observed the presence of Cx43 in COCs with expanded cumulus cells, implying that some level of communication remains between the oocyte and cumulus cells after maturation. The presence of gap junctional coupling in COCs post maturation, as evidenced by the Cx43 expression in mature COCs, might indicate that the communication between the oocyte and the cumulus cells and/or among the cumulus cells via gap junctions is necessary for providing the metabolic support, and possibly for oocyte pick-up by the infundibulum, transport of the oocyte through the oviduct and fertilization (Sutovsky et al 1993, Eppig et al 1997, Lam et al 2000. However, this subject requires further studies.…”

Oviduct: roles in fertilization and early embryo development

“…The filaments of the extracellular matrix from cumulus cells adhere to the glycocalyx at the entrance of the ciliary crowns at the epithelial cells of the infundibulum (Lam et al 2000). Then, the COC is drawn into the oviduct and is ready for fertilization.…”

The effect of cigarette smoke on fertilization and pre-implantation development: assessment using animal models, clinical data, and stem cells

“…This process, called cumulus expansion, facilitates the escape of the oocyte from the antrum of the follicle during ovulation (Talbot, 1983). The secreted matrix enables the OCC to stick to the surface of the infundibulum of the oviduct and then migrate into the ampulla, where fertilization occurs (Lam et al, 2000;Talbot, Gieske & Knoll, 1999). Expansion also separates cumulus cells from each other clearing a pathway of low resistance through which sperm can penetrate and reach the zona pellucida (Talbot et al, 1985).…”

“…OCC pick-up requires adhesion between the tips of the cilia and the cumulus matrix, and factors that increase or decrease adhesion inhibit the rate of pick-up (Lam et al, 2000;Mahi-Brown & Yanagimachi, 1983;Norwood & Anderson, 1980). Inhalation of either MS or SS smoke prior to and during pregnancy increased the number of blebs on the oviductal epithelium of hamsters indicating smoke targets these cells (Magers et al, 1995).…”