scholarly journals Capillaries of the adrenal cortex possess aminopeptidase A and angiotensin-converting-enzyme activities

1980 ◽  
Vol 186 (2) ◽  
pp. 605-608 ◽  
Author(s):  
P J Del Vecchio ◽  
J W Ryan ◽  
A Chung ◽  
U S Ryan
Keyword(s):  
Adrenal Gland ◽  
Angiotensin Converting Enzyme ◽  
Adrenal Cortex ◽  
Enzyme Activities ◽  
Capillary Endothelium ◽  
Converting Enzyme ◽  
Angiotensin I ◽  
Aminopeptidase A

The enzymes required to convert the prohormone angiotensin I into angiotensins II and III, secretagogues of aldosterone, are enriched in association with capillary endothelium isolated from rat adrenal cortex. Thus the secretion of aldosterone may be controlled, in part, by processing of peptides occurring within the adrenal gland itself.

Functional role of local angiotensin-converting enzyme (ACE) in adrenal catecholamine secretion in vivo

1999 ◽  
Vol 77 (11) ◽  
pp. 878-885 ◽  
Author(s):  
Nobuharu Yamaguchi ◽  
Daniel Martineau ◽  
Stéphane Lamouche ◽  
Richard Briand
Keyword(s):  
Angiotensin Ii ◽  
Adrenal Gland ◽  
Angiotensin Converting Enzyme ◽  
Venous Blood Flow ◽  
Dependent Manner ◽  
Converting Enzyme ◽  
Left Adrenal Gland ◽  
Angiotensin I ◽  
Aortic Blood

The aim of the present study was to investigate whether exogenous angiotensin I (AngI) is locally converted to angiotensin II (AngII), which in turn results in an increase in the adrenal catecholamine (CA) secretion in the adrenal gland in anesthetized dogs. Plasma CA concentrations in adrenal venous and aortic blood were determined by an HPLC-electrochemical method. Adrenal venous blood flow was measured by gravimetry. Local administration of AngI (0.0062 to 6.2 µg, 0.0096 to 9.6 µM) to the left adrenal gland resulted in significant increases in CA output in a dose-dependent manner. Following administration of 0.62 µg (0.96 µM) of AngI, adrenal epinephrine and norepinephrine outputs increased from 20.8 ± 13.6 to 250.9 ± 96.4 ng·min-1·g-1 (p < 0.05, n = 5) and from 2.8 ± 1.7 to 29.6 ± 11.1 ng·min-1·g-1 (p < 0.05, n = 5), respectively. From the same left adrenal gland, the output of AngII increased from -0.02 ± 0.04 to 26.39 ± 11.38 ng·min-1·g-1 (p < 0.05, n = 5), while plasma concentrations of AngII in aortic blood remained unchanged. In dogs receiving captopril (12.5 µg, 0.5 mM) 10 min prior to AngI, the net amounts of CA and AngII secreted during the first 3 min after AngI were diminished by about 80% (p < 0.05, n = 5) compared with those obtained from the control group. There was a close correlation (r2 = 0.91, n = 6) between the net increases in AngII and CA outputs induced by AngI. The results indicate that the local angiotensin converting enzyme is functionally involved in regional AngII formation in the canine adrenal gland in vivo. The study suggests that AngII thus generated may play a role in the local regulation of adrenal CA secretion.Key words: angiotensin I, angiotensin II, captopril, adrenal gland, anesthetized dog.

Enkephalinase and angiotensin converting enzyme activities in human venous and arterial plasma

Neuropeptides ◽  
1986 ◽  
Vol 8 (2) ◽  
pp. 111-117 ◽  
Author(s):  
Maria Grazia Spillantini ◽  
Alessandro Panconesi ◽  
Pier Luigi Del Bianco ◽  
Federigo Sicuteri
Keyword(s):  
Angiotensin Converting Enzyme ◽  
Enzyme Activities ◽  
Converting Enzyme ◽  
Arterial Plasma

scholarly journals Pulmonary Capillary Endothelium-Bound Angiotensin-Converting Enzyme Activity in Acute Lung Injury

Circulation ◽  
2000 ◽  
Vol 102 (16) ◽  
pp. 2011-2018 ◽  
Author(s):  
Stylianos E. Orfanos ◽  
Apostolos Armaganidis ◽  
Constantinos Glynos ◽  
Ekaterini Psevdi ◽  
Panagiotis Kaltsas ◽  
...  
Keyword(s):  
Enzyme Activity ◽  
Acute Lung Injury ◽  
Lung Injury ◽  
Angiotensin Converting Enzyme ◽  
Capillary Endothelium ◽  
Converting Enzyme ◽  
Angiotensin Converting Enzyme Activity ◽  
Pulmonary Capillary

scholarly journals Renin-angiotensin-aldosterone system inhibitors – a realm of confusion in COVID-19

2021 ◽  
Vol 4 (Special2) ◽  
pp. 389-394
Author(s):  
Angela Madalina Lazar
Keyword(s):  
Angiotensin Ii ◽  
Angiotensin Converting Enzyme ◽  
Current Knowledge ◽  
Angiotensin Receptor Blockers ◽  
Protective Effects ◽  
Converting Enzyme ◽  
Angiotensin I ◽  
Renin Angiotensin Aldosterone System ◽  
Renin Angiotensin ◽  
Raas Inhibitors

Currently, there is a persisting dispute regarding the renin-angiotensin-aldosterone-system (RAAS) inhibitors' safety of use in COVID-19 pandemics. On one side, RAAS inhibitors appear to determine an overexpression of ACE2, the receptor of SARS-CoV-2. Therefore, they could increase the risk of SARS-CoV-2 infection and its degree of severity. On the other side, the discontinuation of RAAS leads to cardiovascular decompensation and has been discouraged by the major medical societies. Also, large-cohort studies report beneficial or at least neutral effects for the RAAS inhibitors in COVID-19 patients. Worldwide, millions of patients receive RAAS inhibitors for the treatment of hypertension and other important comorbidities. In this context, knowledge of the exact effect of these medications becomes of crucial significance. This paper aims to fill in a gap in the current knowledge and presents a putative mechanism by which RAAS inhibitor administration's beneficial results can be explained better. RAAS inhibitors can be beneficial, as they counteract the excessive detrimental activation of the classical angiotensin-converting enzyme (ACE) axis, decreasing the angiotensin II levels. The angiotensin receptor blockers (ARBs) increase the angiotensin II levels, while the angiotensin-converting enzyme inhibitors (ACEI) increase the angiotensin I levels; these substrates will compete with the SARS-CoV-2 for the ACE2 binding, decreasing the viral infectivity. In addition, following the RAAS inhibitors treatment, the up-regulated ACE2 will cleave these substrates (angiotensin I and II), particularly to angiotensin 1-7 that possesses vasodilator, protective effects.

scholarly journals Angiotensin-Converting Enzyme C-Terminal Catalytic Domain Is the Main Site of Angiotensin I Cleavage In Vivo

Hypertension ◽  
2008 ◽  
Vol 51 (2) ◽  
pp. 267-274 ◽  
Author(s):  
Sebastien Fuchs ◽  
Hong D. Xiao ◽  
Christine Hubert ◽  
Annie Michaud ◽  
Duncan J. Campbell ◽  
...  
Keyword(s):  
Angiotensin Converting Enzyme ◽  
Catalytic Domain ◽  
Converting Enzyme ◽  
Angiotensin I ◽  
Main Site

In vivo measurement of coronary circulation angiotensin-converting enzyme activity in humans

2003 ◽  
Vol 284 (1) ◽  
pp. H17-H22 ◽  
Author(s):  
Cezar Staniloae ◽  
Andreas J. Schwab ◽  
André Simard ◽  
Richard Gallo ◽  
Ihor Dyrda ◽  
...  
Keyword(s):  
Angiotensin Converting Enzyme ◽  
Coronary Circulation ◽  
Coronary Vessels ◽  
Capillary Endothelium ◽  
Converting Enzyme ◽  
In Vivo Measurement ◽  
Atherosclerotic Burden ◽  
Wide Range ◽  
Ace Activity

Angiotensin-converting enzyme (ACE) is present on the luminal surface of the coronary vessels, mostly on capillary endothelium. ACE is also expressed on coronary smooth muscle cells and on plaque lipid-laden macrophages. Excessive coronary circulation (CC)-ACE activity might be linked to plaque progression. Here we used the biologically inactive ACE substrate3H-labeled benzoyl-Phe-Ala-Pro ([3H]BPAP) to quantify CC-ACE activity in 10 patients by means of the indicator-dilution technique. The results were compared with atherosclerotic burden determined by coronary angiography. There was a wide range of CC-ACE activity as revealed by percent [3H]BPAP hydrolysis (30–74%). The atherosclerotic extent scores ranged from 0.0 to 66.97, and the plaque area scores ranged from 0 to 80 mm2. CC-ACE activity per unit extracellular space ( V max/ K m V i), an index of metabolically active vascular surface area, was correlated with myocardial blood flow ( r = 0.738; P = 0.03) but not with measures of the atherosclerotic burden. These results show that CC-ACE activity can be safely measured in humans and that it is a good marker of the vascular area of the perfused myocardium. It does not, however, reflect epicardial atherosclerotic burden, suggesting that local tissue ACE may be more important in plaque development.

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