Work

Endogenous angiotensin concentrations in specific intrarenal fluid compartments of the rat.

Year: 1990

Type: article

Abstract: To examine angiotensin (ANG) concentrations in fluid compartments near known intrarenal ANG receptors, we measured ANG concentrations in glomerular filtrate (GF), star vessel plasma (SVP), and luminal fluid from the early, mid, and late proximal tubule (E, M, and L PT). Samples were collected from euvolemic Munich-Wistar rats by free-flow micropuncture; ANG concentrations were measured by RIA. In one group of rats, concentrations of total immunoreactive ANG (reflecting ANG II and lesser amounts of three fragments) in GF and E, M, and L PT fluid averaged 29-40 nM compared with 32 pM in systemic plasma. In a second group, immunoreactive ANG concentrations in SVP also exceeded systemic levels by a factor of 1,000. In a final group, samples of GF and LPT fluid were purified by HPLC before RIA to measure ANG II and III concentrations specifically: their respective concentrations were 6-8 nM and 14-25 nM. We interpret these results to indicate that substantial amounts of ANG peptides are released into or generated within intrarenal fluid compartments, in which local ANG is likely to effect regulation of renal function independently of systemic ANG.

Source: Journal of Clinical Investigation

DOI: 10.1172/jci114846

Authors: M G Seikaly, B S Arant, F D Seney

Institution: The University of Texas Southwestern Medical Center

Language: English

Topic: Renin-Angiotensin System Studies

Subfield: Cardiology and Cardiovascular Medicine

Field: Medicine

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: bronze

Funders: American Heart Association, National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Diseases