[Prolactin osmoregulatory function in fishes and its projection on mammals].

Prolactin evolution and key role in fish osmoregulation were reviewed. Comparison of fish and mammalian prolactin was made in respect of its structure, producing tissues, regulation of pituitary secretion. Peculiarities of prolactin receptor structure and prolactin-induced signal cascades, tissue distribution and regulation of prolactin receptor expression were compared in fishes and mammals. Data on mechanisms of prolactin action on ionoconservation in teleost fishes at the level of gills, kidney, intestine, and skin were presented. The facts of prolactin participation in the regulation of water and salt balance in mammals were observed. The existence of fundamentally similar mechanisms of osmoregulatory prolactin action in fishes and mammals was accumed and algorithm of their investigation was suggested.