Altered Regulation of Aquaporin-2 Water Channels in the Kidney Following Acute Blood Volume Depletion in Rats.
- Author:
Ying Shun LI
1
;
Yoonwha OH
;
Sungsu LEE
;
Jong Un LEE
Author Information
1. Department of Physiology, Chonnam National University Medical School, Gwangju, Korea. julee@chonnam.ac.kr
- Publication Type:Original Article
- Keywords:
Aquaporin;
Blood volume;
Kidney
- MeSH:
Animals;
Aquaporin 2*;
Aquaporins*;
Blood Volume*;
Blotting, Western;
Body Weight;
Hemorrhage;
Humans;
Hypovolemia;
Kidney*;
Male;
Polymerase Chain Reaction;
Rats*;
Rats, Sprague-Dawley;
Reverse Transcription;
RNA, Messenger
- From:Korean Journal of Nephrology
2003;22(1):37-42
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
BACKGROUND: The present study was aimed to examine the regulation of aquaporin (AQP)-2 water channels in the kidney following blood volume depletion. METHODS: Male Sprague-Dawley rats were acutely blood volume-depleted by withdrawal of arterial blood up to 2% of body weight. The expression of AQP2 mRNA and protein was determined by reverse transcription - polymerase chain reaction and Western blot analysis, respectively, in the inner medulla of the kidney 1 and 3 hours after the hemorrhage. RESULTS: The mRNA expression of AQP2 was significantly increased 1 hour after the bleeding. However, neither the shuttling nor the total abundance of AQP2 proteins was significantly altered. On the contrary, 3 hours after the bleeding, the expression of AQP2 proteins as well as that of AQP2 mRNA was significantly increased. The shuttling of AQP2 proteins was also increased. CONCLUSION: These results suggest that an increased expression of AQP2 channels in the kidney may confer one of compensatory mechanisms restoring the circulating volume in an acute hypovolemic state.