Diminished expression of sodium transporters in the ureteral obstructed kidney in rats.
OBJECTIVE
Whether the postobstructive natriuresis and diuresis is related with an altered regulation of sodium transporters in the kidney was examined.


METHODS
Male Sprague-Dawley rats underwent either bilateral (BUO) or unilateral obstruction (UUO) of the proximal ureters for 24 h. The expression of Na,K-ATPase, type-3 sodium-hydrogen exchanger (NHE3), type-1 bumetanide-sensitive sodium cotransporter (BSC1), and thiazide-sensitive sodium cotransporter (TSC) proteins was determined in the obstructed kidney by Western blot analysis and immunohistochemistry. Catalytic activity of Na,K-ATPase was also determined.


RESULTS
The expression of alpha1 and beta1 subunit proteins and the catalytic activity of Na,K-ATPase were significantly decreased in the obstructed kidney in BUO. The expressions of NHE3, BSC1 and TSC proteins were also significantly decreased. Immunohistochemistry confirmed the downregulation of these sodium transporters in the obstructed kidney. In UUO, the expression of sodium transporters was similarly decreased in the obstructed kidney.


CONCLUSIONS
The postobstructive natriuresis and diuresis may in part be accounted for by a reduced abundance of sodium transporters in the kidney.
Kim
Soo Wan
SW
Department of Physiology, Chonnam National University Medical School, Gwangju, Korea.
Lee
JongUn
J
Jung
Kwon
K
Ma
Seong Kwon
SK
Oh
YoonWha
Y
Kim
Wan-Young
WY
Choi
Ki Chul
KC
Kim
Jin
J
D000818:Animals; D002352:Carrier Proteins / Q000276:immunology / Q000378:metabolism; D004231:Diuresis; D007150:Immunohistochemistry; D016623:Ion Pumps / Q000378:metabolism*; D007668:Kidney / Q000378:metabolism*; D008026:Ligation; D008297:Male; D009318:Natriuresis; D051381:Rats; D017207:Rats, Sprague-Dawley; D011955:Receptors, Drug / Q000276:immunology / Q000378:metabolism; D049992:Sodium Chloride Symporters; D000074083:Sodium-Hydrogen Exchanger 3; D017923:Sodium-Hydrogen Exchangers / Q000276:immunology / Q000378:metabolism; D028021:Sodium-Potassium-Chloride Symporters / Q000276:immunology / Q000378:metabolism; D000254:Sodium-Potassium-Exchanging ATPase / Q000276:immunology / Q000378:metabolism; D064466:Solute Carrier Family 12, Member 1; D064486:Solute Carrier Family 12, Member 3; D027981:Symporters; D014513:Ureter / Q000601:surgery
D002352:Carrier Proteins; D016623:Ion Pumps; D011955:Receptors, Drug; C578716:Slc12a1 protein, rat; C578876:Slc12a3 protein, rat; C000613387:Slc9a3 protein, rat; D049992:Sodium Chloride Symporters; D000074083:Sodium-Hydrogen Exchanger 3; D017923:Sodium-Hydrogen Exchangers; D028021:Sodium-Potassium-Chloride Symporters; D064466:Solute Carrier Family 12, Member 1; D064486:Solute Carrier Family 12, Member 3; D027981:Symporters; C064415:thiazide receptor; D000254:Sodium-Potassium-Exchanging ATPase