Molecular Targets of Natriuretic Action of Prolactin in the Rat Model of Cholestasis of Pregnancy.

We analyzed the expression of molecular targets of natriuretic action of prolactin in different layers of the kidney in the rat model of cholestasis of pregnancy. Sodium bicarbonate cotransporter NBCe1 was most sensitive to the conditions of cholestasis and cholestasis of pregnancy: the expression NBCe1 mRNA and protein in the renal outer medulla decreased in comparison with the normal. All forms of cholestasis affected the mRNA expression of sodium-potassium chloride co-transporter NCC, α-subunit of the ENaCα epithelial sodium channel, and Nedd4-2 ubiquitin ligase in different layers of the kidney.

Prolactin Signaling Pathways Determining Its Direct Effects on Kidneys in the Cholestasis of Pregnancy Model.

Cholestasis of pregnancy is a pathology associated with disruptions in the bile flow and dysregulation of salt and water homeostasis. Prolactin is one of the most important regulators of salt and water balance. Changes in the expression of long and short isoforms of the prolactin receptor (PrlR) and mediators of prolactin signaling were studied by immunoblotting and RT-qPCR in the rat kidney cortex and outer medulla in the model of cholestasis of pregnancy.

Role of Na+/K-ATPase in Natriuretic Effect of Prolactin in a Model of Cholestasis of Pregnancy.

Participation of Na+/K+-ATPase in the natriuretic effect of prolactin in a cholestasis of pregnancy model was investigated. The Na+/K+-ATPase activity in rat kidney medulla, where active sodium reabsorption occurs, decreased in the model of cholestasis of pregnancy and other hyperprolactinemia types compared with intact animals. This effect was not connected with the protein level of α1- and β-subunits of Na+/K+-ATPase measured by Western blotting in the kidney medulla.

Role of Prolactin in the Regulation of Bicarbonates Biodynamics in Female Rat Model of Cholestasis of Pregnancy.

We studied possible involvement of prolactin in the regulation of bicarbonate biodynamics using female rat model of cholestasis of pregnancy induced by transplantation of the donor pituitary under the renal capsule of a recipient (hyperprolactinemia) and bile duct ligation (cholestasis). The concentration of bicarbonates in the bile and blood, their excretion, clearance, and reabsorption, as well as glomerular filtration rate and excretion of sodium ions were assessed. It was found that the main effect of prolactin was directed to the kidney-regulated pool of bicarbonates and consisted in stimulation of their clearance and inhibition of reabsorption, which led to a decrease in bicarbonate blood concentration.

[The state of homeostasis system in patients with aplastic anemia in the period of full-fledged clinical manifestation of disease].

In most cases the immediate cause of lethal outcomes of aplastic anemia is increased hemorrhage. The multifactorial causality of development of hemorrhagic syndrome is to be taken into account to receive informative and accessible characteristics in assessing the state of homeostasis system in patients with aplastic anemia during acute period of disease. The comprehensive analysis of homeostasis system indicators during acute course of aplastic anemia established such characteristic alterations as the presence of signs of activation of homeostasis system, decrease of factor XIII level, inhibition of fibrinolysis system, qualitative deficiency of platelets in peripheral blood.