Summary
The influence of hypothyroidism on both pituitary and serum FSH has been studied in male rats thyroidectomized in early stages of development. To know whether FSH alterations are produced by changes of the gonadal feed-back system or by a direct effect of thyroid hormones upon pituitary synthesis, estradiol, testosterone and testicular weight were measured. The result showed a decrease of biological and immunological activity of pituitary FSH in thyroidectomized rats. Serum FSH levels were also low. The deficiency of FSH production cannot be attributed to an alteration of the gonadal feed-back systems, since (1) in thyrodectomized rats, estradiol and testosterone were lower than in the controls, (2) signs of tubular atrophy were found in the testes and hence it could be expected that inhibin is low, and (3) in the absence of gonadal factors (induced by orchidectomy) thyroidectomized rats also showed a decrease of pituitary FSH. The present data suggest that the decrease of FSH can be attributed to a direct effect of thyroid hormones on pituitary FSH production.
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Bruni JF, Marshall S, Dibbet JA, Meites J (1975) Effects of hyper- and hypothyroidism on serum LH and FSH levels in intact and gonadectomized male and female rats. Endocrinology 97:558–566
Chandrasekar Y, D'Occhio MJ, Setchell BP (1986) Reproductive hormone secretion and spermatogenic function in thyroidectomized rams receiving graded doses of exogenous thyroxine. J Endocrinol 111:245–253
Daane TA, Parlow AF (1971) Preovulatory patterns of rat serum follicle-stimulating hormone during the normal estrous cycle: Effect of pentobarbital. Endocrinology 88:653–663
De la Balze FA, Arrillaga F, Mancini RE, Janches M, Davidson OW (1962) Male hypogonadism: A study of six cases. J Clin Endocrinol 22:215–229
Diebel ND, Yakamoto M, Bogdanove EM (1973) Discrepancies between radioimmunoassay and bioassay for rat FSH: evidence that androgen treatment and withdrawal can alter bioassay-radioimmunoassay ratios. Endocrinology 92:1065–1078
Finney DJ (1978) Statistical methods in biological assay, Griffin, London, pp 227–253
Gordon GG, Southern AL, Tochimoto S, Rand JJ, Olivo J (1969) Effects of hyperthyroidism and hypothyroidism on the metabolism of testoterone and androstendione in man. J Clin Endocrinol Metab 29:164–170
Kalland GA, Vera A, Peterson M, Swerdloff RS (1978) Reproductive hormonal axis of the male rats in experimental hypothyroidism. Endocrinology 102:476–484
Larochelle FT Jr, Freeman ME (1974) Superimposition of thyroid hormone regulation on gonadotrophin secretion. Endocrinology 95:379–386
Naftolin F, Ryan KJ (1975) The metabolism of androgens in central neuroendocrine tissues. J Steroid Biochem 6:993–998
Nakamura H, Yokota T, Imura H, De Groot LJ (1985) Early effect of thyroid hormone on cytosolic protein phosphorilation in rat anterior pituitary. Acta Endocrinol 109:326–329
Schneeberg NG (1967) The thyroid gland and menstrual disorders. In: Israel SL (ed) Diagnosis and treatment of menstrual disorders and sterility. Hoerber, New York, pp 275–300
Steelman SL, Pohley FM (1963) Assay of the follicle-stimulating hormone based on the ovarian augmentation with human chorionic gonadotropin. Endocrinology 53:604–610
Stewart-Bentley M, Odel WD (1974) The feed-back control of luteinizing hormone in normal adult man. J Clin Endocrinol Metab 38:545–551
Valle LBS, Oliveira-Filho RM, Romaldini JH, Lara PF 61985) Pituitary-testicular axis abnormalities in immature male hypothyroid rats. J Steroid Biochem 23:253–257
Wong CC, Dohler KD, Muhlen AVZ (1980) Effects of tri-iodothyroinine, thyroxine and iso-propyl-di-iodothyronine on thyroid stimulatin hormone in serum and pituitary gland and on pituitary concentration of prolactin, growth hormone, luteinizing hormone and follicle-stimulating hormone in hypothyroid rats. J Endocrininol 87:255–264
Yosha S, Fay M, Longcope C, Breverman LE (1984) Effect of D-thyroxine on serum-sexhormone-binding globulin (SHBG), testosterone and pituitary-thyroid function in euthyroid subjects. J Endocrinol Invest 7:489–496
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Ruiz, M., Diego, A.M., Reyes, A. et al. Influence of thyroidectomy on serum and pituitary FSH in control and orchidectomized rats. Res. Exp. Med. 189, 85–90 (1989). https://doi.org/10.1007/BF01851258
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DOI: https://doi.org/10.1007/BF01851258