[Effect of steroid hormones and oxytocin on NO and H2O2 production in the endometrium].

The time and concentration regularities of influence of based estrogens (estrone), hystogenes (progesterone) and their analogs (ecdysterone and diethylstilbestrole) on production of NO and H2O2 by endometrium stroma cells. The level of NO2- in the cell suspension was determined on Grees reactive response, and H2O2 by permanganate measurements in paravariation with the use of horse-radisch peroxidase. It is supposed, that the studied steroids in the experiment conditions affect both the constitutive enzyme systems (membrane or nongenomic phase of activity), and the level of a gene expression (actynomycin D sensitive) and their activity is connected with the rising of concentration of cytosolic Ca2+ in cells. It is shown, that progesterone in hormonal concentrations boosts biosynthesis of NO and H2O2, in comparison with estrone, both in real time of signalling events in the cells (5-30 s), and at long-term action (1-3 h) more effectively. The analogs of steroid hormones, ecdysterone and diethylstilbestrole, were considerably by characterized less effect. The obtained results allow to assume a prime role of progesterone in mechanisms of the endometrium-dependent relaxation of the myometrium. Peptide hormone oxytocine reduces NO production by endometrium and destroys the conforming promoting effect of progesterone, that can testify to the important role of endometrium in processes of initiation of contractile activity of a uterus in labors. The form and amplitude of changes of NO and H2O2 concentration specific for each of studied agonists dilate essentially potentialities of the biological information transmission and allow distinguishing more in detail the external signals and to differentiate the response of cells to various external stimulants. Nitrogen oxide plays an essential role in our system both in the real time of signalling events in cells, and under long-term action, whereas hydrogen peroxide--only at the first stage.