Photoaffinity labeling of pituitary gonadotropin releasing hormone receptors during the rat estrous cycle

Abstract

A bioactive photoaffinity derivative of gonadotropin releasing hormone was used to identify pituitary gonadotropin releasing hormone receptors at various stages of the rat estrous cycle. Sodium dodecyl sulfate polyacrylamide gel electrophoresis resulted in the identification of a single specific component with an apparent molecular weight of 60,000 daltons throughout the estrous cycle. The amount of radioactivity incorporated into the 60K dalton band in diestrus and proestrus female rats increased 2.5-fold to that of metestrus and estrus female rats. These findings provide additional evidence for the identification of pituitary gonadotropin releasing hormone receptors.