Skip to main content

Vasopressin-dependent upregulation of aquaporin-2 gene expression in aged rats with glucocorticoid deficiency

Buy Article:

$43.00 plus tax (Refund Policy)

Abstract Aim: 

The study was undertaken to determine whether ageing affects kidney expression of the aquaporin-2 (AQP2) water channel in glucocorticoid-deficient rats. Methods: 

After adrenalectomy, 6- and 52-week-old Sprague–Dawley rats received aldosterone via osmotic minipumps (glucocorticoid-deficient rats). Aldosterone and dexamethasone were administered to control rats of the same age. Results: 

An acute water load test verified impairment of water excretion in both young and aged rats with glucocorticoid deficiency, with a more serious impairment in the older rats. Despite the presence of hypoosmolality, non-suppressible release of arginine vasopressin (AVP) was particularly evident in the aged rats with glucocorticoid deficiency in comparison with the young rats. The expression levels of AQP2 mRNA and protein were lower in the aged rats, with a particularly large reduction in AQP2 protein expression. AQP2 expression levels were significantly augmented in the glucocorticoid-deficient rats compared with the controls under both basal and water-loaded conditions. Acute water loading did not suppress expression of AQP2 mRNA and protein, and the percentage increases in AQP2 mRNA and protein expression vs. the respective controls were more pronounced in the 52-week-old glucocorticoid-deficient rats compared with the 6-week-old rats. Conclusion: 

The findings indicate that upregulation of AQP2 expression is maintained dependent upon non-suppressible release of AVP in rats with glucocorticoid deficiency, and that AQP2 plays a crucial role in persistent impairment of water excretion in aged rats with glucocorticoid deficiency.
No References
No Citations
No Supplementary Data
No Article Media
No Metrics

Keywords: ageing; aquaporin-2; arginine vasopressin; impaired water excretion; water channel

Document Type: Research Article

Affiliations: 1:  Department of Medicine, Jichi Medical University Saitama Medical Center, Saitama, Japan 2:  Department of Nephrology, Tokyo Medical and Dental University, Tokyo, Japan

Publication date: 01 June 2009

  • Access Key
  • Free content
  • Partial Free content
  • New content
  • Open access content
  • Partial Open access content
  • Subscribed content
  • Partial Subscribed content
  • Free trial content
Cookie Policy
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more