Effect of Dibenzyline on the metabolic actions of epinephrine and thyroxine

Several investigators have attempted to use Dibenzyline to block the metabolic effect of thyroxine as a test of the "epinephrine hypothesis" of thyroxine function. The assumption underlying the use of the drug is that it blocks the hypermetabolism which follows epinephrine administration. This has been tested experimentally and found not to be justified. Dibenzyline does not block specifically the metabolic rate response as measured at 30 C to epinephrine, thyroxine, or a combination of the two hormones. Dibenzyline, thyroxine, and epinephrine show numerous interactions on rate of metabolism, blood glucose, and rectal and surface temperatures, but the Dibenzyline experiments are probably not meaningful in elucidating the role of epinephrine in the peripheral effects of thyroxine.