LACTOGENIC RECEPTORS ON BOVINE GRANULOSA-CELLS

The dependence of binding of bovine prolactin by bovine granulosa cells on the diameter of antral follicles was investigated. The data suggest that granulosa cells express one population of low-affinity prolactin binding sites. There was no significant change in the parameters of interaction of bovine prolactin with lactogenic binding sites during folliculogenesis. Recombinant bovine somatotropic hormone and bovine prolactin compete for binding to the lactogenic binding sites, suggesting that the effects of both hormones can be mediated by the same binding sites on bovine granulosa cells.