Beneficial effect of thyroxin on recovery from toxic acute renal failure

Abstract

To determine the effect of thyroxin (T4) on the recovery from toxic acute renal failure, rats were injected, subcutaneously, with K-dichromate (15 mg/kg) and at the peak of the renal injury, each animal was given either T4 (4 μg/100 g body weight, i.p.) or normal saline (NS). The T4-treated rats had significantly better C(In) (669 ± 35 μl/min/100 g body weight), improved FE(Na) (0.49 ± 0.05%) and increased U(Osm) (835 ± 50 mOsm/kg) as compared to animals given only NS (C(In 422 ± 27; FE(Na) 1.02 ± 0.12; and U(Osm) 613 ± 23). A similar dose of T4 given to non-injured control rats had no effect on renal function. The beneficial effect of T4 on dichromate injected rats was sustained and lead to more prompt recovery of glomerular function. To eliminate any hemodynamic effects of T4, an isolated perfused kidney preparation was utilized, and kidneys from dichromate injected rats treated with T4 had significantly better C(In), urine flow and FE(Na) compared to rats given NS. Cellular morphology was better preserved in T4 treated animals. These data indicate that treatment with T4 results in enhanced recovery from an acute toxic renal tissue and that this beneficial effect is unlikely to be related to nonspecific systemic effects of the hormone.