Effect of nicotine on the maternal systemic and intrarenal adaptations during pregnancy

Abstract

Nicotine causes several changes in renal function, including reduction of glomerular filtration rate (GFR), renal plasma flow (RPF) and increase in renal vascular resistance. The tubular transport of ions and the activity of Na-K ATPase pump are also affected by nicotine. Pregnancy is accompanied by adaptations of the maternal organism including vasodilatation and intrarenal elevation in RPF and GFR. Moreover, retention of salt and water by the kidneys is essential to increase blood volume. Although the effects of prenatal exposure to nicotine on fetal development are well known, few studies are directed to its effects on the maternal adaptation to pregnancy particularly on the renal and systemic changes induced by gestation. As nicotine levels within the kidney are high the aim of the present study is to evaluate the effects of nicotine administration before and during pregnancy in Wistar rats. Virgin and fourteen days pregnant rats will be treated with saline or nicotine for 14 or 28 days. The treatment will be accomplished by subcutaneous implantation of mini pumps with slow release of nicotine. It will be evaluated the effects of nicotine on renal function, tubular transporters of ions and water, systemic parameters and the behavior of the vasodilators hormones involved in the intrarenal adaptation to pregnancy, such as relaxin and nitric oxide.