Effects of acetazolamide and anordiol on osmotic water permeability in AQP1-cRNA injected Xenopus oocyte.
OBJECTIVE
To study the effects of acetazolamide and anordiol on osmotic water permeability in aquaporin 1 (AQP1)-cRNA injected Xenopus oocyte and their mechanisms.


METHODS
AQP1 gene constructed in pBluescript was transcripted into cRNA in vitro and then the cRNA was injected in Xenopus oocytes. The effects of acetazolamide and anordiol on the water transport function of AQP1 were observed by assaying the osmotic swelling of oocytes. In addition, their effects on protein expression of AQP1 were quantitatively investigated by Western blotting method.


RESULTS
After incubation for 15 min or 72 h, acetazolamide, a carbonic anhydrase inhibitor, equally reduced the water permeability of AQP1-cRNA injected oocyte in a dose-dependent manner. After incubation for 72 h, anordiol, an antiestrogen with partial estrogenic activity, reduced the osmotic water permeability dose dependently as well; however, no discernable action was observed after incubation with anordiol for 15 min. The Western blotting analysis showed that acetazolamide did not influence the protein expression of AQP1. However, after incubation for 72 h with anordiol (10 micromol/L), the quantity of AQP1 in the oocyte membrane was decreased dramatically (P<0.05).


CONCLUSIONS
Both acetazolamide and anordiol inhibited the osmotic water permeability of AQP1-cRNA injected oocyte, but their mechanisms were different. Acetazolamide functionally inhibited the osmotic water permeability of AQP1, whereas anordiol primarily decreased the amount of AQP1 protein in the oocyte membrane.
Ma
Bing
B
Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing 100083, China.
Xiang
Yang
Y
Mu
Sheng-Mei
SM
Li
Tao
T
Yu
He-Ming
HM
Li
Xue-Jun
XJ
D000086:Acetazolamide / Q000494:pharmacology*; D000818:Animals; D051398:Aquaporin 1; D020346:Aquaporins / Q000378:metabolism / Q000493:pharmacokinetics*; D002257:Carbonic Anhydrase Inhibitors / Q000494:pharmacology; D002463:Cell Membrane Permeability / Q000187:drug effects*; D005260:Female; D009635:Norandrostanes / Q000494:pharmacology*; D009865:Oocytes / Q000166:cytology / Q000378:metabolism; D009995:Osmosis / Q000187:drug effects; D018075:RNA, Complementary / Q000493:pharmacokinetics; D014982:Xenopus laevis
D020346:Aquaporins; D002257:Carbonic Anhydrase Inhibitors; D009635:Norandrostanes; D018075:RNA, Complementary; D051398:Aquaporin 1; C023615:anordiol; D000086:Acetazolamide