Physiological Mechanisms of Pregnancy: How the Kidneys and the Renin-Angiotensin System Protect the Fetus
Abstract
Physiological changes concurrent with pregnancy include plasma volume expansion with increased sodium retention to enable normal development of the fetus. Expansion of plasma volume and sodium reabsorption are adaptive mechanisms that occur in response to the altered physiological state of pregnancy. These adaptations are mediated by the renin-angiotensin system (RAS) and its primary hormone, angiotensin (Ang) II, acting on the kidney. The role of Ang II in the kidney also involves stimulation of aldosterone release from the adrenal gland, which promotes sodium retention by the kidney. Ang II activates its two main receptors in the kidneys: AT1 and AT2. The AT1 receptor regulates sodium retention rates as well as blood pressure, while the AT2 receptor generally opposes AT1 actions. The aim of this study is to evaluate the role of the RAS in the kidneys of pregnant rats that enables a successful pregnancy. It is of interest to determine if the adaptive mechanisms during pregnancy involve altered expression of AT1 and AT2 receptors. Kidney AT1 and AT2 receptors are measured using radioligand binding assays. Receptor expression is measured in three regions of the kidney and the adrenal gland in both pregnant and nonpregnant rats. We hypothesize that increased AT1 and AT2 receptor expression is associated with increased sodium and water retention rates as well as blood flow in the kidney. The information gained from this study can lead to development of drugs that can benefit pregnant women who have physiological barriers interrupting the renal adaptations necessary for normal fetal development.
Faculty Sponsors
Dr. Robert Speth
Project Type
Event
Location
Alvin Sherman Library
Start Date
4-6-2022 12:00 PM
End Date
4-7-2022 5:00 PM
Physiological Mechanisms of Pregnancy: How the Kidneys and the Renin-Angiotensin System Protect the Fetus
Alvin Sherman Library
Physiological changes concurrent with pregnancy include plasma volume expansion with increased sodium retention to enable normal development of the fetus. Expansion of plasma volume and sodium reabsorption are adaptive mechanisms that occur in response to the altered physiological state of pregnancy. These adaptations are mediated by the renin-angiotensin system (RAS) and its primary hormone, angiotensin (Ang) II, acting on the kidney. The role of Ang II in the kidney also involves stimulation of aldosterone release from the adrenal gland, which promotes sodium retention by the kidney. Ang II activates its two main receptors in the kidneys: AT1 and AT2. The AT1 receptor regulates sodium retention rates as well as blood pressure, while the AT2 receptor generally opposes AT1 actions. The aim of this study is to evaluate the role of the RAS in the kidneys of pregnant rats that enables a successful pregnancy. It is of interest to determine if the adaptive mechanisms during pregnancy involve altered expression of AT1 and AT2 receptors. Kidney AT1 and AT2 receptors are measured using radioligand binding assays. Receptor expression is measured in three regions of the kidney and the adrenal gland in both pregnant and nonpregnant rats. We hypothesize that increased AT1 and AT2 receptor expression is associated with increased sodium and water retention rates as well as blood flow in the kidney. The information gained from this study can lead to development of drugs that can benefit pregnant women who have physiological barriers interrupting the renal adaptations necessary for normal fetal development.
