Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.6.1.3 (ATPase)
 65,361 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Na+-K+-ATPase was inhibited by 1 times 10-4M ethacrynic acid and mercuderamide, and by 1 times 10-3M hydrochlorothiazide and furosemide. A modification of Gilman's (1970) protein displacement assay has been used to measure c-AMP levels in toad bladder epithelial cells. Vasopressin (50 mU/ml) caused c-AMP levels to rise from 4.27 to 9.27 pmol/mg protein. Ethacrynic acid had no effect on cellular c-AMP levels after 10 min exposure to the drug, but at 90 min caused a reduction of both basal and vasopressin stimulated levels. Furosemide caused an apparent rise in c-AMP levels, dilution ratio measurements indicated interference by this drug in the assay procedure, mecuderamide also caused substantial interference with the c-AMP assay. Hydrochlorothiazide had no effect on basal or hormone stimulated levels of c-AMP. It was concluded that the inhibition of sodium transport produced by ethacrynic acid in toad bladder is probably due to inhibition of adenylate cyclase, an effect not shared by other dieuretics.
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PMID:The effect of diuretics on Na+-K+-ATPase and c-AMP levels in toad bladder epithelial cells. 16 90

To study the short-term uptake of potassium across the basolateral membrane into individual tubule cells, rubidium was used and measured by electron microprobe analysis. Changes of rubidium uptake were interpreted to reflect altered sodium entry and basolateral Na-K-ATPase activity. The effects of hydrochlorothiazide, amiloride and furosemide were determined in saline-loaded animals. Hydrochlorothiazide inhibited rubidium uptake in proximal convoluted and distal convoluted tubule cells. The effect was largest in distal convoluted tubule cells. Amiloride reduced rubidium uptake in principal cells as well as in proximal convoluted, distal convoluted and connecting tubule cells. Furosemide depressed rubidium uptake in distal convoluted tubule cells, but increased uptake in principal cells. Rubidium uptake into intercalated cells was not affected by any of the diuretics used. Hydrochlorothiazide and amiloride altered rubidium uptake also in cells not associated with the main diuretic action. These effects of hydrochlorothiazide and amiloride may be due to interference with cell transport mechanisms of Na-H and anion exchange.
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PMID:Effect of diuretics on cell potassium transport: an electron microprobe study. 216 64

The effects of diazoxide and hydrochlorothiazide on vasopressin-induced increments in osmotic water flow and sodium transport across the frog bladder were studied. Diazoxide enhanced the vasopressin-induced osmotic water flow of the bladder, but did not affect the cyclic AMP- or theophylline-induced water flow. Hydrochlorothiazide did not affect the vasopressin-induced water flow. Our results suggest that diazoxide increased the water flow by inhibiting the activity of phosphodiesterase in bladder epithelial cells, whereas hydrochlorothiazide did not. On the other hand, both drugs suppressed the short-circuit current of the bladder membrane and inhibited the Na,K-dependent ATPase activity of the kidney cells. These results suggest that both drugs decreased sodium transport in the bladder by inhibiting Na,K-dependent ATPase activity.
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PMID:Effects of diazoxide and hydrochlorothiazide on water permeability and sodium transport in the frog bladder. 628 Feb 12