Radioimmunoassay and characterization of renin-angiotensin system in the fresh-water turtle

✍ Scribed by Cho, Kyung Woo ;Kim, Suhn Hee ;Koh, Gou Young

• Publisher: John Wiley and Sons
• Year: 1987
• Tongue: English
• Weight: 624 KB
• Volume: 242
• Category: Article
• ISSN: 0022-104X
• DOI: 10.1002/jez.1402420303

✦ Synopsis

We developed a radioimmunoassay (RIA) for plasma renin concentration (PRC) and characterized the renin-angiotensin system BAS) in the fresh-water turtle (A mydajaponica).

Among three antisera to human angiotensin I (ANG I) had different specificities to ANG I analogues; the antiserum with the highest specificity was used to measure the PRC. The amount of ANG I generated from incubation of turtle renal extracts with turtle plasma was linear with respect to volume of renal extract and incubation time. Turtle renin cleaved heterologous substrates from nephrectomized rats and rabbits but had a higher affinity for renin substrate from rabbits. The generation of ANG I with heterologous substrate was temperature dependent (optimum-37°C) and the pH optimum was at 5.0-5.5. Furosemide (5 mgkg) did not affect PRC. Hemorrhage (1% and 3% of body weight) decreased blood pressure. The PRC did not change with the lower hemorrhage, but increased significantly with massive hemorrhage. Angiotensin I1 increased blood pressure with no effect in PRC. The PRC of fresh-water