Response to LH-RH in men infused with theophylline

In an attempt to ascertain certain aspects of the effects of cyclic AMP on the release of LH and FSH in the human being, ten normal men were tested with LH-RH during the infusion of theophylline, a methyl xanthine derivative which inhibits the inactivation of cyclic AMP by phosphodiesterase. The results were compared with the gonadotropin values obtained when LH-RH was injected into the same subjects without theophylline. Although no consistent effect of theophylline was found on either the basal levels of LH and FSH or the magnitude of their increase after LH-RH, an action of cyclic AMP on gonadotropin release is not excluded.