The activity of prolylcarboxypeptidase (PCP), or angiotensinase C, was measured in lung tissues, leukocytes, and cultured human cells using Cbz-Pro-[14C]Ala as a substrate. A lysosomal fraction of homogenized rat or human lung contained most of the PCP activity in that tissue. Polymorphonuclear neutrophils, macrophages, and lymphocytes isolated from human blood had PCP activity. Fibroblasts cul...

The protean properties of 20-hydroxyeicosatetraenoic acid (HETE), vasoactivity, mitogenicity, and modulation of transport in key nephron segments, serve as the basis for the essential roles of 20-HETE in the regulation of the renal circulation and electrolyte excretion and as a second messenger for endothelin-1 and mediator of selective renal effects of ANG II. Renal autoregulation and tubular ...

The renin–angiotensin system (RAS) has an important role in the control of blood pressure, hypertension, diabetes, and in the regulation of salt and volume homeostasis of organisms as well as in the heart failure, and other related renal dysfunctions. Renin is the main protease enzyme of the RAS. In kidney, Juxtaglomerular (JG) cells are most important site for renin production. Renin act on An...

Recent studies have reported potential roles of angiotensins in an adaptative physiological mechanism of protection against cerebral ischemia-induced neurological damages. In the present study, we examined the protective role of angiotensin IV (AngIV) in a rat model of embolic stroke induced by intracarotid injection of calibrated microspheres (50 microm). Internal carotid infusions of increasi...

Angiotensin tachyphylaxis is rapidly induced in the mesenteric vascular circuit of the rat perfused with a saline solution. there is crossed tachyphylaxis among angiotensins (AI, AII, and AIII). The angiotensin antagonist Sar 1-Ileu 8-AII is ineffective when the vascular preparation is previously rendered tachyphylactic to AII, showing that the AII receptors are not available during tachyphylax...

Cerebral catecholamines and angiotensins are both involved in the regulation of cardiovascular function. Recent in vitro studies have suggested that angiotensin II modulates noradrenergic neurotransmission by controlling both the expression and neuritic trafficking of tyrosine hydroxylase (TH), the rate-limiting enzyme in catecholamine biosynthesis. To assess the potential existence of such mec...

Previous work on the brackish-water crab Chasmagnathus granulatus demonstrated that an endogenous peptide similar to angiotensin II plays a significant role in enhancing long-term memory that involves an association between context and an iterative danger stimulus (context-signal memory). The present results show that this memory enhancement could be produced by moving crabs from brackish water...

1. Changes in arterial blood pressure, blood angiotensin I, plasma angiotensin II and plasma angiotensin III were measured in conscious sodium-depleted dogs after infusion of captopril, an orally active inhibitor of converting enzyme. 2. Angiotensins II and III were measured after chromatography to remove angiotensin I, which increased in concentration after inhibition of converting enzyme and ...

BACKGROUND AND PURPOSE Recent investigations indicated that degradation fragments of angiotensins could be involved in the regulation of the cerebral circulation and that their effects might be mediated by prostaglandins. The present study was designed to examine the effect of angiotensin-(1-7), a major endogenous heptapeptide fragment, on cerebral arteriolar diameter and compare it with the oc...

Increases in arterial pressure and paraventricular nucleus vasopressin release in response to intracerebroventricular injections of angiotensin peptides are blunted in mRen2(27) renin transgenic [TG(+)] rats. Intraventricular injections of tachykinin peptides mimic several of the actions of angiotensin peptides, and angiotensin peptides evoke substance P release from hypothalamic brain slices. ...