Occurrence and Properties of a Prostaglandin F2α Receptor in Bovine Corpora Lutea

Abstract

Prostaglandin F_2α was specifically bound by a particulate fraction from bovine corpora lutea. The rate constants for the association (7.5×10³ M⁻¹s⁻¹) and dissociation (2.1×10⁻⁴s⁻¹) reactions gave a dissociation constant of 2.8×10⁻⁸ M which is similar to that determined from a Scatchard plot of binding data at equilibrium (5×10⁻⁸ M). The receptor was stable for several hours at 23°C but was rapidly destroyed at 37°C. The pH optimum for the binding reaction was 6.3. The receptor had high specificity for prostaglandin F_2α and had much lower affinities for other prostaglandins. Luteinizing and follicle-stimulating hormones had no effect on the prostaglandin F_2α-receptor interaction.