Angiotensin II is a vasoactive peptide that may affect vascularization of the ischemic heart via angiogenesis. In this study we aimed at studying the mechanisms underlying the angiogenic effects of angiotensin II under hypoxia in the mouse heart in vitro. Endothelial sprout formation from pieces of mouse hearts was assessed under normoxia (21% O(2)) and hypoxia (1% O(2)) during a 7-day period o...

NO produced by NO synthase type 3 (NOS3) in medullary thick ascending limbs (mTHALs) inhibits Cl(-) reabsorption. Acutely, angiotensin II stimulates thick ascending limb NO production. In endothelial cells, NO inhibits NOS3 expression. Therefore, we hypothesized that angiotensin II decreases NOS3 expression via NO in mTHALs. After 24 hours, 10 and 100 nmol/L of angiotensin II decreased NOS3 exp...

Increased activity of the renin angiotensin system with enhanced levels of angiotensin II leads to oxidative stress with endothelial dysfunction, hypertension, and atherosclerosis. Epidemiologic studies revealed a higher cancer mortality and an increased kidney cancer incidence in hypertensive patients. Because elevated angiotensin II levels might contribute to carcinogenesis, we tested whether...

To understand how vertebrates utilize angiotensins during evolutionary development, we undertook studies to synthesize and/or characterize angiotensin-like peptides from nonmammalian species. The present paper describes the synthesis of [Asp1,Val5,Asn9] angiotensin I (bull frog, Rana catesbeiana) (I), [Asn1,Val5,His9] angiotensin I (Japanese goosefish, Lophius litulon) (II), [Asn1, Val5,Asn9] a...

Studies of the baroreceptor-heart rate reflex were performed in four conscious, unrestrained male baboons to determine whether changes in circulating angiotensin II within the physiological range are associated with alterations in baroreceptor reflex sensitivity. With the animals on a high sodium intake, studies were performed before and during graded angiotensin II infusion (10 and 20 ng/kg/mi...

Can the Study of Female Rats Help Our Understanding of Women? To the Editor: Sampson et al1 are to be congratulated for their important contribution to knowledge of the effects of gender on the effects of angiotensin peptides. Importantly, their study showed in rats that low-dose angiotensin II reduced blood pressure in females but not in males, and this blood pressure reduction was mediated by...

The effects of changes in glomerular filtration rate and renal blood flow on the renal handling of Cor '"l-labeled angiotensin II were studied in pentobarbitai-anesthetized dogs. Labeled angiotension II was injected as a bolus directly into the renal artery and the renal venous effluent was collected. Under control conditions, 52 ± 8% of the labeled material recovered was angiotensin II and the...

The present studies were designed to examine the effect of angiotensin II on baroreflex control of adrenocorticotropic hormone secretion and heart rate in conscious dogs. Baroreflex function was assessed by examining the relationship between blood pressure and plasma corticosteroid concentration (used as an index of adrenocorticotropic hormone secretion) and between blood pressure and pulse int...

Hypertension is associated with an increased risk of thrombosis that appears to involve an interaction between the renin-angiotensin system and hemostasis. In this study we determined whether angiotensin II-mediated thrombosis occurs in arterioles and/or venules and assessed the involvement of type 1 (AT₁), type 2 (AT₂), and type 4 (AT₄) angiotensin II receptors, as well as receptors for endoth...