Aldosterone Rapidly Enhances Levels of the Striatin and Caveolin-1 Proteins in Rat Kidney: The Role of the Mineralocorticoid Receptor
10.3803/EnM.2019.34.3.291
- Author:
Kevalin INTHACHART
1
;
Krissanapong MANOTHAM
;
Somchai EIAM-ONG
;
Somchit EIAM-ONG
Author Information
1. Interdepartment of Physiology, Chulalongkorn University Graduate School, Bangkok, Thailand.
- Publication Type:Original Article
- Keywords:
Aldosterone;
Rapid action;
Striatin;
Caveolin 1;
Protein levels;
Rat kidney
- MeSH:
Aldosterone;
Animals;
Blotting, Western;
Caveolin 1;
Humans;
Hypertension;
Immunohistochemistry;
Kidney;
Male;
Rats;
Rats, Wistar;
Receptors, Mineralocorticoid;
Sodium;
Sodium Chloride;
Water
- From:Endocrinology and Metabolism
2019;34(3):291-301
- CountryRepublic of Korea
- Language:English
-
Abstract:
BACKGROUND: Striatin and caveolin-1 (cav-1) are scaffolding/regulating proteins that are associated with salt-sensitive high blood pressure and promote renal sodium and water reabsorption, respectively. The mineralocorticoid receptor (MR) interacts with striatin and cav-1, while aldosterone increases striatin and cav-1 levels. However, no in vivo data have been reported for the levels of these proteins in the kidney. METHODS: Male Wistar rats were intraperitoneally injected with normal saline solution, aldosterone alone (Aldo: 150 µg/kg body weight), or aldosterone after pretreatment with eplerenone, an MR blocker, 30 minutes before the aldosterone injection (eplerenone [Ep.]+Aldo). Thirty minutes after the aldosterone injection, the amount and localization of striatin and cav-1 were determined by Western blot analysis and immunohistochemistry, respectively. RESULTS: Aldosterone increased striatin levels by 150% (P<0.05), and cav-1 levels by 200% (P<0.001). Eplerenone had no significant effect on striatin levels, but partially blocked the aldosterone-induced increase in cav-1 levels. Aldosterone stimulated striatin and cav-1 immunoreactivity in both the cortex and medulla. Eplerenone reduced cav-1 immunostaining in both areas; however, striatin intensity was reduced in the cortex, but increased in the medulla. CONCLUSION: This is the first in vivo study demonstrating that aldosterone rapidly enhances renal levels of striatin and cav-1. Aldosterone increases striatin levels via an MR-independent pathway, whereas cav-1 is partially regulated through MR.
