title: Stimulation of Na+/K(+)-ATPase activity by polyamines in the rat renal medullary cells of the thick ascending limb of Henle's loop.
abstract: Previous studies have indicated that ornithine decarboxylase (ODC) may be involved in the stimulation of Na+/K(+)-ATPase activity by arginine vasopressin (AVP) in the rat renal medullary thick ascending limb of Henle's loop. The present study was aimed at establishing the role of the polyamines, the conversion products of ODC activity, in the stimulation of Na+/K(+)-ATPase by AVP. Using cytochemical methods, we have demonstrated an increase in Na+/K(+)-ATPase activity after stimulation with putrescine, spermidine and spermine (each 1 mmol/l) for 2.5, 2 and 1.5 min respectively. The specific inhibitors of spermidine and spermine synthase, bis-cyclohexylammonium sulphate and N-alkylated-1,3-diaminopropane respectively, inhibited the stimulation of Na+/K(+)-ATPase by AVP, this inhibition being reversed by spermine. These findings suggest that polyamines are involved in the stimulus-response coupling of the hormone-mediated response.
authors.affiliation: Department of Medicine, Medical School, University of Newcastle upon Tyne.
authors.forename: J A
authors.initials: JA
authors.lastname: Charlton
authors.forename: P H
authors.initials: PH
authors.lastname: Baylis
mesh_terms: D000818:Animals; D001127:Arginine Vasopressin / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D005260:Female; D006651:Histocytochemistry; D007668:Kidney / Q000201:enzymology; D007679:Kidney Medulla / Q000187:drug effects / Q000201:enzymology; D008138:Loop of Henle / Q000187:drug effects / Q000201:enzymology*; D009924:Organ Culture Techniques; D009955:Ornithine Decarboxylase / Q000378:metabolism*; D011073:Polyamines / Q000494:pharmacology*; D011700:Putrescine / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism*; D013095:Spermidine / Q000494:pharmacology; D013096:Spermine / Q000494:pharmacology; D013268:Stimulation, Chemical
chemical_list: D011073:Polyamines; D001127:Arginine Vasopressin; D013096:Spermine; D009955:Ornithine Decarboxylase; D000254:Sodium-Potassium-Exchanging ATPase; D013095:Spermidine; D011700:Putrescine