Oestrogen-induced increase in uterine cGMP content in vitro: effects of inhibitors of protein and RNA synthesis.
We have shown previously that oestradiol elevates the cGMP content od isolated uterine horns incubated for 2 h with the hormone. Cycloheximide (30 micrograms/ml) or actinomycin D (100 micrograms/ml), at concentrations which markedly inhibit protein and RNA synthesis, blocked the oestrogen-induced increase in cGMP. These agents do not inhibit the rise in uterine cGMP content provoked by sodium nitroprusside, thus arguing against a direct toxic effect on the enzyme guanylate cyclase. alpha-Amanitin, even at very high concentrations (80 micrograms/ml), interfered much less efficiently with total RNA and protein synthesis and also failed to prevent the oestrogen-induced increase in cGMP content. Taken together, these observations indicate that oestrogen action on uterine cGMP concentration in vitro depends on an RNA and/or a protein biosynthetic event that takes places in the uterus. This therefore confirms and extends analogous observations made previously under conditions in vivo.
D000818:Animals; D006152:Cyclic GMP / Q000032:analysis*; D003513:Cycloheximide / Q000494:pharmacology*; D003609:Dactinomycin / Q000494:pharmacology*; D004967:Estrogens / Q000494:pharmacology*; D005260:Female; D066298:In Vitro Techniques; D009599:Nitroprusside / Q000494:pharmacology; D014176:Protein Biosynthesis; D012313:RNA / Q000096:biosynthesis*; D051381:Rats; D011919:Rats, Inbred Strains; D014599:Uterus / Q000032:analysis / Q000187:drug effects*
D004967:Estrogens; D009599:Nitroprusside; D003609:Dactinomycin; D012313:RNA; D003513:Cycloheximide; D006152:Cyclic GMP