Ruth A. Young

Familial Dysalbuminemic Hyperthyroxinemia

Abstract We investigated 15 euthyroid patients from eight families with a recently recognized syndrome, familial dysalbuminemic hyperthyroxinemia (FDH), that could be mistaken for thyrotoxicosis. T...

Familial dysalbuminemic hyperthyroxinemia associated with primary thyroid disease

This study describes a family with intrinsic thyroid disease in addition to familial dysalbuminemic hyperthyroxinemia, a syndrome associated with euthyroidism and increased binding of thyroxine to serum albumin. The simultaneous occurrence of thyroid disease and elevated serum thyroxine concentrations due to familial dysalbuminemic hyperthyroxinemia may confound the diagnosis of the two concurrent disorders and the subsequent therapy of the thyroid disease.

Interrelationships between body weight, food consumption and plasma thyroid hormone concentration cycles in the woodchuck, Marmota monax

The interrelationships between body weight, food consumption and plasma thyroid hormone concentrations were studied during the spring, summer and fall in two groups of woodchucks: those allowed to eat ad libitum and those kept at their March weight by food restriction. The food consumption of the ad libitum fed control animals was greatest in April and May and then declined. Body weight in these animals peaked in July and then slowly declined during the rest of the study. When the restricted animals were allowed to eat ad libitum in August they rapidly increased their food consumption and brought their body weight up to that of the controls in less than six weeks. Plasma thyroxine (T4) and triiodothyronine (T3) concentrations decreased during the summer in the control animals and then rose again in the fall. The T4 changes were blunted in the restricted animals. T3 concentrations decreased during the summer in the restricted animals and remained low until one month after they were allowed to eat ad libitum. The low plasma concentrations of T3 during the summer in the woodchuck may facilitate weight gain in preparation for hibernation.

The effects of low-protein diet and testosterone on sex hormone-binding globulin capacity in male rabbits☆

The effects of a low-protein high-carbohydrate (LPHC) diet (8% protein 65% to 72% carbohydrate) were compared to those of regular rabbit chow (14% to 16% protein 57% to 64% carbohydrate) on sex hormone-binding globulin (SHBG) capacity in 12 male rabbits. The six rabbits who were fed the LPHC diet for 8 weeks showed a significant increase in their mean SHBG capacity (mean +/- SE: from 70 +/- 16 nmol/L to 332 +/- 45 nmol/L, P less than .01) whereas the six rabbits fed the standard diet showed a slight decrease (from 106 +/- 22 nmol/L to 76 +/- 20 nmol/L, NS). These changes in SHBG capacity were mirrored by a decrease in percent-free T (from 2.64 +/- 0.26% to 1.64 +/- 0.16%, P less than .01) in the LPHC diet group and no change in percent-free T in the regular diet group (from 2.36 +/- 0.21% to 2.19 +/- 0.10%). The changes in SHBG capacity and percent-free T were not associated with significant changes in testosterone (T), free T, estradiol (E2), thyroxine, triiodothyronine, thyroxine-binding globulin, or cortisol binding globulin levels. In a subsequent experiment, testosterone cyclopentyl propionate (TCP) was administered to six male rabbits while on regular rabbit chow and again after 6 weeks of the LPHC diet. TCP administration did not cause any significant change in the SHBG capacity, but the LPHC resulted again in a significant (P less than .05) increase in SHBG capacity from 80 +/- 18 nmol/L. to 198 +/- 22 nmol/L.(ABSTRACT TRUNCATED AT 250 WORDS)