The effect of spironolactone on transport of Na+, K+ and H+. A microperfusion study in rat main submaxillary duct.
The epithelium of the main excretory duct of the rat submaxillary gland was used as a target tissue for studies on the effect of a spironolactone on electrolyte transport. The spironolactone decreased net Na+ reabsorption by 27% and net K+ secretion by 23%. HCO-3 was found to be about 2-fold accumulated in the duct lumen, which was considered to result from decreased H+ion secretion. The results can be reconciled with an action of spironolactone on 1) the peritubular Na+-K+-exchange mechanism and 2) the functional coupling of Na+ entry from lumen to cell with K+ and H+ transfer from cell to lumen.
D000818:Animals; D001639:Bicarbonates / Q000378:metabolism; D001693:Biological Transport, Active / Q000187:drug effects; D002191:Canrenoic Acid / Q000494:pharmacology; D008297:Male; D011188:Potassium / Q000378:metabolism*; D051381:Rats; D012964:Sodium / Q000378:metabolism*; D013148:Spironolactone / Q000494:pharmacology*; D013363:Submandibular Gland / Q000187:drug effects* / Q000378:metabolism
D001639:Bicarbonates; D013148:Spironolactone; D002191:Canrenoic Acid; D012964:Sodium; D011188:Potassium