Endocrinol Metab.  2019 Sep;34(3):291-301. 10.3803/EnM.2019.34.3.291.

Aldosterone Rapidly Enhances Levels of the Striatin and Caveolin-1 Proteins in Rat Kidney: The Role of the Mineralocorticoid Receptor

Affiliations
  • 1Interdepartment of Physiology, Chulalongkorn University Graduate School, Bangkok, Thailand.
  • 2Department of Medicine, Lerdsin General Hospital, Bangkok, Thailand.
  • 3Division of Nephrology, Department of Medicine, Chulalongkorn University Faculty of Medicine, Bangkok, Thailand.
  • 4Department of Physiology, Chulalongkorn University Faculty of Medicine, Bangkok, Thailand. eiamong@yahoo.com

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.

Keyword

Aldosterone; Rapid action; Striatin; Caveolin 1; Protein levels; Rat kidney

MeSH Terms

Aldosterone*
Animals
Blotting, Western
Caveolin 1*
Humans
Hypertension
Immunohistochemistry
Kidney*
Male
Rats*
Rats, Wistar
Receptors, Mineralocorticoid*
Sodium
Sodium Chloride
Water
Aldosterone
Caveolin 1
Receptors, Mineralocorticoid
Sodium
Sodium Chloride
Water
Full Text Links
  • ENM
Actions
Cited
CITED
export Copy
Close
Share
  • Twitter
  • Facebook
Similar articles
    DB Error: unknown error