[Effect of synthetic analogs of the sex steroid hormones on the secretory and proliferative activity of the adenohypophysis in vivo and in vitro in rats]. / Izuchenie vliianiia sinteticheskikh analogov polovykh steroidnykh gormonov na sekretornuiu i proliferativnuiu aktivnost' adenogipofiza krys in vivo i in vitro.

Synthetic steroid compounds STS 557 and STS 737 administered to ovariectomized rats increased prolactin secretion to a lesser extent than estradiol benzoate or estrogen J 271. When injected to estradiol benzoate treated ovariectomized rats, compounds STS 557, STS 737 and progesterone failed to change DNA synthesis in the adenohypophysis and prolactin secretion. Only compound STS 737 exerted a pronounced effect on the adenohypophyseal cells in primary cultures. It inhibited DNA synthesis and prolactin secretion. These effects were synergistic with the inhibitory action of bromocriptine (CB-154) that is of certain interest for elaborating methods of treatment of pituitary hyperplasias and tumours.

[Growth and development of pre-implantation rat embryos in vitro. Effect of various hormonal factors]. / Rost i razvitie pred'implantatsionnykh embrionov krysy in vitro. Vliianie nekotorykh gormonal'nykh faktorov.

The effect of 17 beta-estradiol and polypeptides of hypophyseal origin (prolactin, adenohypophysis cell culture secretion products) on the development of 5-day rat embryos in vitro was studied. Preimplantation rat embryos grew and developed normally in medium 199 enriched with 10% embryonic calf serum. The addition into this medium of estradiol in the concentrations of 10(-6) M, 10(-8) M or prolactin (0.01 micrograms/ml) did not produce an injuring effect on the growth of embryos incubated in vitro. A clear embryotoxic effect was noted in the incubation of embryos in a medium with high concentrations (0.1-1 microgram/ml) of prolactin or in a 3-day culture of rat adenohypophyseal cells. It may be inferred that the inhibitory effect of high doses of prolactin on embryo development is one of the possible causes of the embryotoxic effect of adenohypophysis cell culture secretion products.