Triiodothyronine enhances renal response to aldosterone in the rabbit collecting tubule.
AUTOR(ES)
Barlet, C
RESUMO
Since thyroid hormones and mineralocorticoids were observed to stimulate kidney Na-K-ATPase in similar sites and with similar time courses, this study was initiated to evaluate whether aldosterone is involved in the stimulation of Na-K-ATPase observed in collecting tubules 3 h after triiodothyronine (T3) administration to thyroidectomized (TX) rabbits. Results indicate that: Plasma aldosterone level decreased markedly in TX rabbits but was not restored 3 h after T3 injection; Early stimulation of Na-K-ATPase by T3 was abolished when plasma aldosterone level was suppressed by adrenalectomy or when aldosterone effects were blocked by spironolactone; Administration of aldosterone to TX rabbits mimicked the action of T3; Sensitivity of Na-K-ATPase to aldosterone markedly decreased after thyroidectomy. These results demonstrate an interaction between aldosterone and T3 in the control of Na-K-ATPase in the collecting tubule. Triiodothyronine enhances the sensitivity of Na-K-ATPase to aldosterone which, in turn, produces a stimulatory action despite the decreased plasma level observed during hypothyroidism.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=424149Documentos Relacionados
- Secondary effect of aldosterone on Na-KATPase activity in the rabbit cortical collecting tubule.
- Transport of ammonia in the rabbit cortical collecting tubule.
- Regulation of intracellular pH in the rabbit cortical collecting tubule.
- Regulation of Cl-/HCO3- exchange in the rabbit cortical collecting tubule.
- Interactions of lysyl-bradykinin and antidiuretic hormone in the rabbit cortical collecting tubule.
