title: Stimulation of rat renal Na+, K+-ATPase activity by thyroid hormones.
abstract: The effect of thyroid hormones (T4, T3 and reverse T3) on rat renal Na+,K+-ATPase activity was investigated by a cytochemical technique. T3 caused stimulation of Na+,K+-ATPase activity in the renal medulla but not in the renal cortex. There was a peak in enzyme activity after cultured renal segments had been exposed to T3 for 11 min and this time of maximal stimulation did not vary with the concentration of T3. A rectilinear response in Na+,K+-ATPase activity was observed over T3 concentration range 10 pmol l-1 to 100 nmol l-1; at higher T3 concentrations, Na+,K+-ATPase activity was inhibited. The enzyme response was totally blocked by specific T3 antiserum. Addition of T4 and reverse T3 (100 fmol l-1 -1 mmol l-1) failed to stimulate Na+,K+-ATPase activity in any part of the kidney. Plasma (neat and diluted 1:10) stimulated the enzyme in parallel with the dose response curve and the stimulatory effect was abolished by prior addition of specific T3 antiserum.
mesh_terms: D000818:Animals; D005260:Female; D066298:In Vitro Techniques; D007668:Kidney / Q000187:drug effects* / Q000201:enzymology; D007672:Kidney Cortex / Q000187:drug effects; D007679:Kidney Medulla / Q000187:drug effects; D051381:Rats; D011919:Rats, Inbred Strains; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism*; D013963:Thyroid Hormones / Q000494:pharmacology*; D013974:Thyroxine / Q000494:pharmacology; D014284:Triiodothyronine / Q000494:pharmacology; D014285:Triiodothyronine, Reverse / Q000494:pharmacology
chemical_list: D013963:Thyroid Hormones; D014284:Triiodothyronine; D014285:Triiodothyronine, Reverse; D000254:Sodium-Potassium-Exchanging ATPase; D013974:Thyroxine