22 PSYCHOTHERAPY : SCIENTIFIC AND RELIGIOUS chap.
exercise a controlling influence over other glands. One of these has been termed the master sex hormone. This secretion seems necessary for the adequate functioning of the gonads of both sexes. A lack of it delays or prevents sexual maturity, an excess often causes precocious puberty, an effect similar to that of the adrenal cortex, except that the pituitary hormone is stimulating to either sex. The pituitary sex hormone and its growTth hormone seem to be antagonistic. In normal individuals a correct balance is maintained, but excessive growth from pituitary disorder is usually accompanied by sexual immaturity, while sexual precocity of the pituitary type often involves stunted growth. The thyrotropic hormone of the pituitary anterior controls the action of the thyroid gland. Recent studies seem to indicate that ' exophthalmic ' goitre, in which the eyeballs protrude, is due primarily to this pituitary hormone, which causes the thyroid to swell and oversecrete, and has a direct effect on the eyes.
Other pituitary hormones control fat and carbohydrate metabolism, one regulates the rate of water exchange of the body, and others have effects still not discovered. The complexity of the problem presented by the pituitary gland is not to be underestimated. Its many hormones are intricately related both among themselves and with the other glands of the body. A further difficulty arises from this gland's close association with the hypothalamus, the lower brain centre which, among other duties, regulates several of the metabolic functions.
One further important disorder which is ascribed to a combination of pituitary deficiencies is Frohlich's disease. This occurs more commonly among boys, who show great obesity but small bone development, a lack of sexual maturity, and general lack of stamina. It has been treated with some success with pituitary extracts.