Increasing evidence suggests that angiotensin II (Ang II) may act as a growth factor for the heart. However, direct effects of Ang II on mammalian cardiac cells (myocytes and nonmyocytes), independent of secondary hemodynamic and neurohumoral effects, have not been well characterized. Therefore, we analyzed the molecular phenotype of cultured cardiac cells from neonatal rats in response to Ang ...

In the present study, we investigated renal microvascular responses to ANG-(1-7) and ANG IV. Diameter changes of small interlobular arteries, afferent arterioles, and efferent arterioles were assessed by using isolated perfused hydronephrotic rat kidneys. ANG-(1-7) and ANG IV concentration dependently decreased the diameters of all investigated renal microvessel, however, with a much lower pote...

Stimulation of renal proximal tubule (PT) transport by angiotensin II (Ang II) is critical for regulation of BP. Notably, in rats, mice, and rabbits, the regulation of PT sodium transport by Ang II is biphasic: transport is stimulated by picomolar to nanomolar concentrations of Ang II but inhibited by nanomolar to micromolar concentrations of Ang II. However, little is known about the effects o...

The effect of cold exposure on the systemic renin-angiotensin system and on regulation of the angiotensin II (Ang II) receptor was examined in target organs for Ang II with cardiovascular relevance (left ventricle, kidney, lung) and metabolic relevance [interscapular brown adipose tissue (ISBAT), liver] to the functional consequences of cold exposure. In time course studies, the effects were ex...

Leptin contributes to the pathogenesis of atherosclerosis. Ang II (angiotensin II), a proatherogenic cytokine, increases leptin synthesis in cultured adipocytes. Statin suppresses leptin expression in adipocytes and human coronary artery endothelial cells. However, the effect of Ang II and statin on leptin expression in VSMCs (vascular smooth muscle cells), the major cell types in atheroma, is ...

Angiotensin (Ang)-(1-7) is a biologically active peptide of the renin-angiotensin system that has both vasodilatory and antiproliferative activities that are opposite the constrictive and proliferative effects of angiotensin II (Ang II). We studied the actions of Ang-(1-7) on the Ang II type 1 (AT(1)) receptor in cultured rat aortic vascular smooth muscle cells to determine whether the effects ...

Angiotensin-converting enzyme 2 (ACE2) catalyzes the conversion of the vasoconstrictor angiotensin II (ANG II) to the vasodilatory peptide angiotensin-(1-7) [ANG-(1-7)]. We showed that treatment of hypertensive rats with the AT(1) receptor antagonist olmesartan increased ACE2 mRNA and protein in the thoracic aorta, suggesting that endogenous ANG II tonically reduces the enzyme. We now report th...

Postural tachycardia syndrome (POTS) is associated with increased plasma angiotensin II (Ang II). Ang II administered in the presence of NO synthase inhibition with nitro-L-arginine (NLA) and Ang II type 1 receptor blockade with losartan produces vasodilation during local heating in controls. We tested whether this angiotensin-mediated vasodilation occurs in POTS and whether it is related to an...

BACKGROUND Several enzymes that hydrolyze angiotensin I (Ang I) and Ang II to Ang-(1-7) have been identified, but their relative importance in the intact human heart is not known. METHODS AND RESULTS Intracoronary (IC) 123I-Ang I was administered to 4 heart transplantation recipients. Arterial and coronary sinus (CS) samples were taken before and after coadministration of IC enalaprilat. 123I...

Angiotensin (Ang) II is implicated in hypertension, vascular remodeling, and insulin resistance. Peroxisome proliferator–activated receptor (PPAR) activators increase insulin sensitivity and improve Ang II–induced vascular remodeling. We evaluated the effects of the PPARactivator rosiglitazone on Ang II signaling in aorta and mesenteric arteries. Rats received Ang II by subcutaneous infusion an...