The effect of goitrogens on the hypothalamic neurosecretion in experimental animals.

Neurosecrets such as vasopressin and oxytocin are believed to be involved in the mechanism(s)of the release of pituitary ACTH and gonadotrophin,respectively (Shibusawa, 1955); and it is well accepted that the thyroid gland is under the control of the pituitary. Only scant attention has, however, been paid on the relation of the hypothalamus to the pituitary-thyroidal function. In terms of hypothalamic lesions, a few investigators have studied the structural alterations in the thyroid or pituitary gland(Greer, 1952, 1955; Scharf, 1955; Martini, 1955). Greer(1952, 1955)reported that the thyroidal response to exogenous thyrotrophin is changed in rats with anterior hypothalamic lesions. We have suggested the possibility of a hypothalamic hurnoral control of the thyrotroph-thyroidal function in the preceding volume of this Journal(Shibusawa et al., 1955). The present experiment was designed in the hope of elucidating the role of neurosecretory phenomenon in causing the hyperand hypo-functions of the thyroid.