1.Blunted Indomethacin-Induced Downregulation of Aquaporins by Nitric Oxide Synthesis Inhibition in Rats.
Ju Hee YOU ; Sungsu LEE ; Eun Hui BAE ; Seong Kwon MA ; Soo Wan KIM ; Jong Un LEE
The Korean Journal of Physiology and Pharmacology 2006;10(4):213-216
The present study was aimed to determine whether nitric oxide (NO) plays a role in the regulation of aquaporin (AQP) channels in the kidney. Male Brattleboro rats (250~300 g body weight) were used. The experimental group was treated with N(G)-nitro-L-arginine methyl ester (L-NAME, 100 mg/L drinking water) for 1 week, and cotreated with indomethacin (5 mg/kg, twice a day, i.p.) for the last two days. Control groups were treated with either L-NAME for 1 week, indomethacin for 2 days, or without any drug treatment. The abundance of AQP1, AQP2 and AQP3 proteins in the kidney was determined by Western blot analysis. Indomethacin downregulated AQP channels, whereas L-NAME by itself showed no significant effects on them. The indomethacin-induced downregulation of AQP2 and AQP3 was significantly blunted in L-NAME-treated rats, while that of AQP1 was not affected. These results suggest that endogenous NO, when stimulated, may downregulate AQP channels that are specifically regulated by AVP/cAMP pathway in the kidney.
Animals
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Aquaporin 3
;
Aquaporins*
;
Blotting, Western
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Down-Regulation*
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Drinking
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Humans
;
Indomethacin
;
Kidney
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Male
;
NG-Nitroarginine Methyl Ester
;
Nitric Oxide*
;
Rats*
;
Rats, Brattleboro