Abstract
Among the results of early hypophysectomy in the anuran larva is marked underdevelopment of the thyroid gland and the adrenal cortex. 1 The resulting condition of the sex-glands has not been adequately studied in amphibia although it is well known for mammals. 2 In attempting to analyze this fairly complex glandular situation from a functional viewpoint it seems important to determine what effects are due primarily to absence of the hypophysis and what secondarily, through impairment of the thyroid, the adrenal cortex, or possibly the gonads. The relationship of the thyroid has been rather definitely established by the following observations: (1) anterior pituitary substance to hypophysectomized tadpoles stimulates the atrophic thyroid and induces metamorphosis; (2) thyroid substance to hypophysectomized tadpoles produces metamorphosis; (3) pituitary substance to hypophysectomized tadpoles which also have been thyroidectomized does not cause metamorphosis. 1 , 3 It is clear that the hypophysis works through the thyroid in this particular reaction.
The functional relationships of the adrenal cortex are not so well known, although it has been shown that pituitary administration restores the atrophied adrenal cortex of the hypophysectomized animal. 1 , 2 Due to its diffuse nature and its intimate anatomical relation to the mesonephros, the amphibian adrenal is not suitable for experimental removal. Until the recent work of Hartman et al, 4 and of Swingle and Pfiffner 5 a potent extract of the adrenal cortex was not available. A relation of the adrenal gland to sex function is suggested by numerous clinical and pathological observations. 6
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