THE RELATION OF ENVIRONMENTAL TEMPERATURE TO THE ACTION OF THYROXINE

Abstract

Expts. conducted during a summer heat-wave or at high room temps. showed that thyroxine was much more toxic for guinea pigs exposed to a high environmental temp. (32[degree] C.) and high humidity than for those kept at a lower temp. (20[degree] C). Gastric ulcers developed frequently when animals were kept at 32[degree] for 2, 4 and 6 wks. and treated with small doses of thyroxine. The loss of body wt. was much greater after treatment at 32[degree] than at 20[degree]. This increase in thyroxine may be due to suprarenal exhaustion.