HORMONAL-REGULATION OF GAP JUNCTION PROTEINS AND ESTROGEN-RECEPTOR ACTIVATION FACTORS IN THE RAT UTERUS

The present study examines the hormonal regulation of the syntheses of gap junction proteins and estrogen receptor activation factors in the rat uterus. Ovariectomy and the depletion of estradiol from the syste m exerted negative influence on the synthesis of both the proteins. At the same time exposure of the ovariectomized rats to exogenous estrad iol resulted in the restoration of protein synthesis back to the contr ol level. A transient peak in the synthesis of the two proteins was ob served on day 2 following ovariectomy. This increased activity was not observed in rats subjected to adrenalectomy along withh ovariectomy. Furthermore, exposure of the ovariectomized plus adrenalectomized rats to progesterone clearly emphasized the point that the increase in the protein synthesis observed on day 2 post-ovariectomy was due to proge sterone released from the adrenals. The results are indicative of a bi -hormonal involvement in the control of the syntheses of the two prote ins, estrogen receptor activation factors and gap junction proteins in the rat uterus.