Studies on renal function in healthy women with different degrees of induced potassium depletion. 3) Effective roles of prostanoids and angiotensin II in hypokalemic renal dysfunction.
By using two similar dietary and pharmacological patterns of potassium depletive treatment, two experimental groups--KD2 (n = 6) and KD3 (n = 6)--with cumulative potassium deficit not significantly different, were obtained. The basal values of plasma potassium concentration and PRA, as well as the expression of renal hypokalemic dysfunction were not significantly different. Paired studies in the absence and presence of indomethacin (KD2 group) or enalapril (KD3 group) were performed. The aim of the research was evaluation of the effective roles of prostanoid and angiotensin (AT) II systems in renal hypokalemic dysfunction. The results show that: 1) AT II and cortical vasodilating prostanoids exerted opposite effects on the preglomerular arteriolar tone; 2) medullary prostanoids antagonized the vasopressin effects. Therefore, in potassium depletion the decreased synthesis of cortical and medullary prostanoids, in the face of the increased generation of AT II, contributed to reducing the glomerular filtration rate and facilitate the expression of vasopressin action. These components of the renal hypokalemic dysfunction probably exert a protective role with regard to the urinary chloride and potassium losses.
Agnoli
G C
GC
Cattedra di Medicina Interna I dell'Università di Bologna.
Borgatti
R
R
Cacciari
M
M
Garutti
C
C
Ikonomu
E
E
Lenzi
P
P
Marinelli
M
M
D000804:Angiotensin II / Q000502:physiology*; D002712:Chlorides / Q000378:metabolism; D003404:Creatinine / Q000097:blood; D004231:Diuresis / Q000187:drug effects; D004656:Enalapril / Q000494:pharmacology; D005260:Female; D006801:Humans; D007008:Hypokalemia / Q000503:physiopathology*; D007213:Indomethacin / Q000494:pharmacology; D007668:Kidney / Q000187:drug effects / Q000503:physiopathology*; D009318:Natriuresis / Q000187:drug effects; D011188:Potassium / Q000378:metabolism*; D017419:Potassium, Dietary / Q000008:administration & dosage; D011453:Prostaglandins / Q000096:biosynthesis / Q000502:physiology*; D014867:Water / Q000008:administration & dosage
D002712:Chlorides; D017419:Potassium, Dietary; D011453:Prostaglandins; D014867:Water; D000804:Angiotensin II; D004656:Enalapril; D003404:Creatinine; D011188:Potassium; D007213:Indomethacin