Mechanism of estrogenaction—Independence of several responses of the rat uterus from the early increase in adenosine 3′,5′-cyclic monophosphat

Estrogen action via the cAMP signaling pathway: stimulation of adenylate cyclase and cAMP-regulated gene transcription.

“…However, there has been increasing evidence for interactions between cAMP and estrogen in enhancing the growth of the mammary gland and breast cancer cells (3, 4) and for cAMP induction of estrogen-like uterine growth (5). As early as 1967, Szego and Davis (6) demonstrated a very rapid, acute elevation of uterine cAMP by estrogen treatment of rats in vivo that was confirmed in other reports (7,8), but several subsequent studies either failed to confirm this observation or reported only minimal effects that were considered to represent indirect effects of estrogen on cAMP mediated by estrogen-induced release of uterine epinephrine (9)(10)(11)(12). Recently, cAMP and other protein kinase activators have been documented to synergize with steroid hormone-occupied receptors, leading to enhanced steroid receptor-mediated transcription (13)(14)(15)(16)(17)(18), possibly by a mechanism involving phosphorylation of the receptor or associated transcription factors (14,(19)(20)(21).…”

Hormone involvement in the establishment of pregnancy

“…It has been argued that such changes are not a direct consequence of oestrogen action, however, and evidence has been presented which indicates that several early uterine responses to oestradiol administration are independent of cyclic AMP mediation (Dupont-Mairesse, Van Sande, Rooryck, Fastrez-Boute & Galand, 1974). A biphasic elevation of cyclic GMP rather than cyclic AMP has been observed by others (Kuehl et al, 1973(Kuehl et al, , 1974Flandroy, Fastrez-Boute & Galand, 1976).…”

PROTEIN KINASES ACTIVATED BY cAMP IN THE GENITAL TRACT OF SPAYED MICE TREATED WITH OESTRADIOL-17

“…The observed increase of the cAMP level in rat uteri after stimulation with oestradiol (Szego & Davis, 1967; Dupont-Mairesse, Van Sande, Rooryck, Fastrez-Boute & Galand, 1974) is relevant to the possible rôle of the cAMPprotein kinase system for the oestradiol effect. Other studies have failed to detect any differences in cAMP level (Sanborn, Bhalla & Korenman, 1973;Zor, Koch, Lamprecht, Ausher & Lindner, 1973), or adenylate cyclase activity (Sanborn, Bhalla & Korenman, 1973) related to oestradiol stimulation.…”