[Effect of sex inversion in embryos of domestic chicken (Gallu gallus domesticus) by influence of letrozole and tamoxifen].

Realization of program of sex formation in multicellular organisms is a complex multistage process. The role of the inductor in this process is assigned to sex hormones synthesized by cells of the emerging gonads. The action of androgens on the formation of the male is now well understood. However, little is known about the involvement of estrogen the female gonad formation and the formation of a female as a whole. Here we present the results of experimental sex inversion in female chickens produced by aromatase inhibition and by the action of tamoxifen on chicken embryos. We have shown various masculinizing effect depending on the dose of active substance and the number of injections. We have noted that inhibition of aromatase does not block meiotic prophase in oogoniums. We have suggested that there are differences in the mechanisms of action of retinoic acid and estrogens on oogenesis. We have first shown proteins and nucleoproteins that interact with the estrogen receptor 1 and provided maps of their gene localization in human and chicken genomes.