EFFECT OF COCULTURE WITH STALLION SPERMATOZOA ON DE-NOVO PROTEIN-SYNTHESIS AND SECRETION BY EQUINE OVIDUCT EPITHELIAL-CELLS

Adhesion of equine spermatozoa to homologous oviduct epithelial cells (OEC) in vitro results in specific changes in spermatozoa and OEC func tion. To test the hypothesis that adhesion of spermatozoa affects prot ein synthesis and secretion by OEC, the following treatment groups wer e established in culture: OEC with culture medium only; control sperma tozoa in culture medium only; OEC in coculture with spermatozoa; and O EC and spermatozoa in coculture, but physically separated by a micropo rous membrane. The experiment was replicated within each of 4 ejaculat es from 3 stallions. De novo protein secretion by OEC was measured and compared by incorporation of [S-35]methionine, and evaluated, using t wo-dimensional polyacrylamide gel electrophoresis and fluorography. Mo nolayers of OEC secreted a large number of proteins of molecular mass ranging from 14 to 205 kd. Adhesion of spermatozoa consistently caused reduced synthesis of 2 OEC secretory proteins and new or increased sy nthesis of 6 proteins. When spermatozoa and OEC were separated by a mi croporous membrane, some but not all of these changes were duplicated. Synthesis of 3 OEC secretory proteins, unaffected by binding of sperm atozoa, was reduced when spermatozoa were prevented from contact with OEC by a microporous membrane. Adhesion of equine spermatozoa to homol ogous OEC monolayers and presence of equine spermatozoa resulted in qu alitative and quantitative changes in synthesis and secretion of prote ins by OEC. These changes have implications for storage, longevity, an d maturation of spermatozoa.