Thyroid,Pituitary,and Hypothalamic Hormone Levels in Neonatal Rat Pups following Maternal Protein Deficiency 1

Summary

Thyroidal, pituitary, and hypothalamic hormones in the plasma and tissues of newborn young of rats fed diets containing 24 or 4% casein as the sole source of protein were quantitated by radioimmunoassay. Circulating levels of total plasma triiodothyronine (T₃) were significantly reduced and the free fraction of T₃ was lower in young of protein-deprived rats than in control pups. Total plasma T_4, free T_4, plasma TSH, pituitary TSH per milligram of pituitary, the metabolic clearance rate of exogenous TSH per 100 g of body weight, and the TRH content of the hypothalamus were not significantly affected by the maternal diet.