Specific binding of prostaglandin F2 alpha to membranes of rat corpora lutea. |
| |
Authors: | K Wright J L Luborsky-Moore H R Behrman |
| |
Affiliation: | Reproductive Biology Section, Department of Obstetrics and Gynecology, Yale University School of Medicine, New Haven, CT 06510 U.S.A. |
| |
Abstract: | Prostaglandin F2 alpha (PGF2 alpha) binds specifically to a partially purified membrane preparation from rat corpora lutea. The high affinity, low capacity binding component asa a Kd = 4.7 nM and has a capacity of 0.38 pmol/mg protein. Binding kinetics were temperature-dependent with an association rate constant of 2.5 x 10(5) 1/mol-sec and a dissociation rate constant of 4.3 x 10(-4) sec-1 at 22 degrees C. Little competition for binding was shown by other prostaglandins and prostaglandin metabolites; the PGF2 alpha analogue ICI 81008 (16-m-trifluoromethylphenyl-prostaglandin F2 alpha) showed a binding affinity similar to that of PGF2 alpha. The specific binding of PGF2 alpha to luteal cell membranes was confirmed by electron microscopy using a ferritin--PGF2 alpha conjugate. Ferritin--PGF2 alpha was found predominantly on luteal cell surfaces; little binding occurred on other types of cells present. These data demonstrate specific binding of PGF2 alha to rat luteal membranes. It is suggested that the luteolytic action of PGF2 alpha in the rat may be receptor-mediated. |
| |
Keywords: | luteolysis receptors ovary corpus luteum hormone binding |
本文献已被 ScienceDirect 等数据库收录! |