Deletion of AT receptors selectively in the proximal tubules of the kidney alters the hypotensive and natriuretic response to atrial natriuretic peptide via NPR/cGMP/NO signaling.

In the proximal tubules of the kidney, angiotensin II (ANG II) binds and activates ANG II type 1 (AT) receptors to stimulate proximal tubule Na reabsorption, whereas atrial natriuretic peptide (ANP) binds and activates natriuretic peptide receptors (NPR) to inhibit ANG II-induced proximal tubule Na reabsorption. These two vasoactive systems play important counteracting roles to control Na reabsorption in the proximal tubules and help maintain blood pressure homeostasis. However, how AT and NPR receptors interact in the proximal tubules and whether natriuretic effects of NPR receptor activation by ANP may be potentiated by deletion of AT (AT) receptors selectively in the proximal tubules have not been studied previously.

Genetic Deletion of AT Receptor or Na/H Exchanger 3 Selectively in the Proximal Tubules of the Kidney Attenuates Two-Kidney, One-Clip Goldblatt Hypertension in Mice.

The roles of angiotensin II (Ang II) AT1 (AT1a) receptors and its downstream target Na+/H+ exchanger 3 (NHE3) in the proximal tubules in the development of two-kidney, 1-clip (2K1C) Goldblatt hypertension have not been investigated previously. The present study tested the hypothesis that deletion of the AT1a receptor or NHE3 selectively in the proximal tubules of the kidney attenuates the development of 2K1C hypertension using novel mouse models with proximal tubule-specific deletion of AT1a receptors or NHE3. 2K1C Goldblatt hypertension was induced by placing a silver clip (0.

The Na/H Exchanger 3 in the Intestines and the Proximal Tubule of the Kidney: Localization, Physiological Function, and Key Roles in Angiotensin II-Induced Hypertension.

The sodium (Na)/hydrogen (H) exchanger 3 (NHE3) is one of the most important Na/H antiporters in the small intestines of the gastrointestinal tract and the proximal tubules of the kidney. The roles of NHE3 in the regulation of intracellular pH and acid-base balance have been well established in cellular physiology using techniques. Localized primarily on the apical membranes in small intestines and proximal tubules, the key action of NHE3 is to facilitate the entry of luminal Na and the extrusion of intracellular H from intestinal and proximal tubule tubular epithelial cells.

Angiotensin II and AT Receptors in the Proximal Tubules of the Kidney: New Roles in Blood Pressure Control and Hypertension.

Contrary to public perception, hypertension remains one of the most important public health problems in the United States, affecting 46% of adults with increased risk for heart attack, stroke, and kidney diseases. The mechanisms underlying poorly controlled hypertension remain incompletely understood. Recent development in the approach to study gain or loss of function of a particular gene has significantly helped advance our new insights into the role of proximal tubule angiotensin II (Ang II) and its AT (AT) receptors in basal blood pressure control and the development of Ang II-induced hypertension.

Sex differences in angiotensin II-induced hypertension and kidney injury: role of AT1a receptors in the proximal tubule of the kidney.

In the present study, we tested the hypothesis that there are significant sex differences in angiotensin II (Ang II)-induced hypertension and kidney injury using male and female wildtype (WT) and proximal tubule-specific AT1a receptor knockout mice (PT-Agtr1a-/-). Twelve groups (n=8-12 per group) of adult male and female WT and PT-Agtr1a-/- mice were infused with a pressor dose of Ang II via osmotic minipump for 2 weeks (1.5 mg/kg/day, i.