DIFFERENT EFFECTS OF hGH AND bGH ON ELECTRON TRANSPORT COMPONENTS OF LIVER MITOCHONDRIA

Abstract

patients'with thyrotoxico~is were seen over the past 21 yrs: the female/male ratio was 4:l. The ages ranged between 2 to 8 years. 28 patients were lost to follow-up and 60 were followed for an average of 3.9 yrs. Family history of thyroid disease was present in 23 patients and was thyrotoxicosis in 12. Of 28 patients (46%) who underwent sub-total thyroidectomy, 13 relapsed after an average of 3 years of medical treatment; 5 had hypersensitivity to Propylthiouracil; 11 showed poor cooperation. Prophylactic thyroid hormone was begun in 5 patients after surgery, and in an additional 8 because of subsequent hypothyroidism. Fourteen had permanent remission on medical treatment, three of whom may have had thyrotoxic thyroiditis. Of the series of 60 one child was referred after treatment with ~~1 1 3 1 , and another died of other causes.Fourteen patients on Propylthiouracil continue to be followed, and the longest duration of medical treatment has been 6 years in one patient. Our experience leads us to employ medical treatment for prolonged periods when there are no complications. The etiology of precocious sexual development in this disease entity has not been identified in vivo, but has been linked (in theory) with a concept of "overflow stimulation" of the anterior pituitary gonadotrophs, and/or of the hypothalamus with resultant releasing factor effects.We have developed a rat hemi-pituitary (pit) organ culture system. Utilizing NIAMD reagents both secreted and added rat LH was measured in medium 199 by radioimmunoassay. Pituitaries from 10 day old males secreted LH at a constant rate of 41.31 mug/hr/mg pit wet wt. ~~C E M with hourly media changes. When Rat LH-RP-1 was added to the media an immediate rise in hourly LH secretion was observed (Day 1, 103.3 ? 28.9; Day 2, 190.67 2 18.65). On Day 2 of culture a dose response was present. The LH-RP-1 contains 0.22 USP (Bovine) TSH Units/mg (McKenzie Assay) which appears to be responsible for the marked stimulation of LH secretion. Differential stimulation studies utilizing purified LH, FSH and TSH will confirm this observation.This study suggests that high endogenous TSH secretion which occurs in primary hypothyroidism has a direct stimulative effect on the gonadotrophs, and is responsible for the precocious sexual development. The suppression of TSH by thyroxine administration and resultant remission of precocity in these patients, further support our findings.FETAL AND NEONATAL DEVELOPMENT OF THE HYPOTHALAMIC-PITUITARY-GONADAL (HPG) AXIS. Herbert L. Vallet, Donna S. Gursky, Lesley S. Baldwin (Intr. by Richard B. Goldbloom), Dalhousie Univ., Dept. of Ped., I.W.K. Hosp. for Child., Halifax, Nova Scotia.A male rat model was developed to study parameters which may relate to the rise in plasma testosterone (T) seen in male human neonates, and also to define the critical period of HP differentiation (male-female types) after which reversal of brain sex centers (acyclicity vs cyclicity) cannot.occur.Animals were studied from 19 days gestation (da gest) to 29 da postnatal ...