Zinc Deficiency, Chronic Starvation, and Hypothalamic-Pituitary-Thyroid Function

Am J Clin Nutr. 1980 Aug;33(8):1767-70. doi: 10.1093/ajcn/33.8.1767.

Abstract

Male Sprague-Dawley rats were fed a zinc-deficient diet to study its effects on the hypothalamic-pituitary-thyroid axis. As zinc-deficient animals fail to gain weight, they were compared to pair-fed growth restricted animals as well as ad libitum fed controls. The growth velocity curves were superimposable for the zinc-deficient animals and the pair-fed controls; both were markedly reduced compared to the ad libitum controls. Both the zinc-deficient and the pair-fed controls had lower triiodothyronine (T3) and thyroxine levels compared to the ad libitum controls. In addition T3 values were lower in the zinc-deficient animals compared to the pair-fed controls (P < 0.05). Hypothalamic thyrotrophin-releasing hormone content was decreased in the zinc-deficient rats (162 +/- 32 pg/ml) compared to the ad libitum controls (305 +/- 102; P < 0.01). The 125I thyroidal uptakes were not significantly different between the zinc-deficient and the pair-fed controls. Zinc deficiency lowers T3 more than comparable caloric restriction; this suggests that zinc deficiency may impair extrathyroidal production of T3.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Hypothalamo-Hypophyseal System / physiopathology*
  • Male
  • Rats
  • Starvation / physiopathology*
  • Thyroid Gland / physiopathology*
  • Thyroid Hormones / blood
  • Zinc / deficiency*
  • Zinc / physiology

Substances

  • Thyroid Hormones
  • Zinc