Effect of Reserpine on Thyroid Activity in Rats.

Abstract

The average thyroid secretion rate (TSR) or rats receiving 5 and 10 [mu]g/100 g reserpine was 0.230 [mu]g/100 g and that of animals injected with 50 [mu]g/100 g was 0.135 [mu]/10Q g 1-thyroxine. This represented a decrease of 84 to 90% when compared with average control values of 1.30 [mu]g/100 g 1-thyroxine. The difference between TSR''s of the high and low reserpine groups was significant (P<.001). The average hourly release of thyroidal 131 (k''4) during the experimental period was significantly less (P <.005) than during the control period at all dosages of reserpine employed. Body weight was reduced markedly in animals receiving 50 /Mg/lOO g reserpine while those rats injected with the two lower doses exhibited significant increases (P< .001) in weight. It is suggested reserpine alters thyroid function through inhibition of thyrotropin secretion.