[Arguments for the existence of an endogenous inhibitor of renal Na-K ATPase with steroid structure and natriuretic action].
In order to explain the opposite effect of 6,7-dihydroxylated isomers of 6, 7 - dihydrocanrenone on the urinary sodium and potassium excretion, we have tested the effect of these substances isolated from human urine on the Na(+)-K+ pump from different tissue preparation: rabbit kidney slices as well as NA-K ATPase purified from the kidney. Our results show an inhibition of pump as well as enzyme activity by the 6 beta 7 alpha isomer while the 2 other isomers are either uneffective or slightly stimulating. The 6 beta 7 alpha dihydroxy-6, 7-dihydrocanrenone could be one of the plasma ouabain-like substance incriminated in the pathogenesis of volume-expanded hypertension.
Krzesinski
J M
JM
Service de néphrologie, CHU Sart-Tilman, Belgique.
Christiaens
L
L
Palem-Vliers
M
M
Fenghe
D
D
Pequeux-Bar
M L
ML
Lomba-Pignon
M R
MR
Genard
P
P
Rorive
G
G
D000818:Animals; D002192:Canrenone / Q000031:analogs & derivatives / Q000494:pharmacology*; D006973:Hypertension / Q000503:physiopathology; D007668:Kidney / Q000201:enzymology*; D009318:Natriuresis / Q000187:drug effects; D011817:Rabbits; D051381:Rats; D000254:Sodium-Potassium-Exchanging ATPase / Q000037:antagonists & inhibitors* / Q000378:metabolism
D002192:Canrenone; D000254:Sodium-Potassium-Exchanging ATPase
Arguments en faveur de l'existence d'un inhibiteur endogène de la Na-K ATPase rénale, de nature stéroïdienne et à vertu natriurétique.