Some Specific and Non-Specific Effects of Thiamine Deficiency in the Rat. ∗

Summary and Conclusions

A detailed study was made of the gross and microscopic organ changes in the thiamine deficient rat as compared to normal and paired weight controls. It was apparent that the deficiency produced the essential changes characteristic of non-specific stress such as adrenal hypertrophy, thymus involution and decreased adrenal ascorbic acid. Marked renal hypertrophy was also observed in the deficient rats and was considered to be due to the prolonged negative nitrogen balance known to be associated with thiamine deficiency. The reduced gonadotrophin and increased adreno-corticotrophine secretion as indicated by the developmental failure of the sex organs and hypertrophy of the adrenals illustrates the so-called “shift” of pituitary hormone production under these circumstances. In contrast to the non-specific changes above, thiamine deficiency showed specific effects on the liver and heart. The activity of the germinal centres of the splenic lymphatic follicles was normally maintained in contra-distinction to the failure of germinal activity previously observed in B-complex deficiency.