[Differential protein analysis in rat renal proximal tubule epithelial cells in response to acetazolamide and its relation with the inhibition of AQP1].
OBJECTIVE
To study the endogenous mechanism for the inhibition of aquaporin-1 expression in rat renal proximal tubule epithelial cells in response to acetazolamide.


METHODS
Primary cultured rat renal proximal tubule epithelia cells were divided into two groups: one was subjected to 1 x 10(-5) mol.L-1 acetazolamide, the other served as normal control. When grown to sub-confluency, the cells were disintegrated to perform isoelectrofocusing electrophoresis in order to find the differential proteins induced by the acetazolamide treatment. The differential proteins were defined by peptide mass fingerprinting technology.


RESULTS
Two differential proteins were found in the cell disintegrant. The pI 3.8 protein was reduced after treatment, which showed 21.4% similarity with the brush border membrane myosin from rat brain and testis, and 27% with glycogen phosphorylase; The pI 5.5 protein was increased on the contrary, with 20% similarity to phosphatidylinositol transfer protein alpha isoform.


CONCLUSIONS
Acetazolamide inhibited AQP1 expression probably by affecting the expression of pI 3.8 and pI 5.5 proteins.
Mu
Sheng-mei
SM
Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing 100083, China.
Ji
Xun-he
XH
Ma
Bing
B
Yu
He-ming
HM
Li
Xue-jun
XJ
D000086:Acetazolamide / Q000494:pharmacology*; D000818:Animals; D051398:Aquaporin 1; D020346:Aquaporins / Q000037:antagonists & inhibitors* / Q000378:metabolism; D004232:Diuretics / Q000494:pharmacology; D004847:Epithelial Cells / Q000378:metabolism*; D007525:Isoelectric Focusing; D007687:Kidney Tubules, Proximal / Q000166:cytology* / Q000378:metabolism; D008297:Male; D010449:Peptide Mapping; D051381:Rats; D017207:Rats, Sprague-Dawley
C496022:Aqp1 protein, rat; D020346:Aquaporins; D004232:Diuretics; D051398:Aquaporin 1; D000086:Acetazolamide