HYPOPHYSIS CEREBRI 339 



pathological changes in the thyroid gland. It is an undoubted 

 fact that, in many of its aspects, acromegaly resembles Graves's 

 disease. Enlargement of the thyroid apparatus is frequently 

 observed in acromegaly, and Lancereaux believed that this condi- 

 tion results from a stimulation of the processes of growth, brought 

 about by the enlarged thyroid gland, and modified and controlled 

 by the hypophysis. As things stand at present, it is difficult to 

 estimate the significance of the part played by the thyroid appa- 

 ratus in acromegaly. That hypothyrosis produces an enlarge- 

 ment of the hypophysis is undoubtedly true, but it can hardly be 

 regarded as the primary cause of such enlargement. There is 

 an equal probability that the hyperpituitarism brings about a 

 reduction of function, and consequent atrophy, on the part of the 

 thyroid. The assumption of an interrelationship between the 

 activities of the two organs is justified by clinical experience, and 

 it remains for experimental pathology to crystallize this assump- 

 tion into a certainty. 



Persistence of the thymus in acromegaly is by no means rare. 

 The inconstancy of the finding, however, deprives this pheno- 

 menon of the causative significance attributed to it by Klebs. 



The relationship between the suprarenals and the hypophysis, 

 especially in acromegaly, has not as yet been sufficiently investi- 

 gated. After extirpation of the suprarenals, Alquier observed 

 signs of moderate hyperplasia of the hypophysis in a dog; Boinet 

 found that hypertrophy was exceptional in rats; while Marenghi 

 found marked hypertrophy in guinea-pigs, rabbits and cats. 

 Hyperplastic changes in the hypophysis have been described in 

 suprarenal disease in man (Thaon, Delille) ; while, on the other 

 hand, adenoma and cystic degeneration of the suprarenals have 

 been observed in acromegaly. Delille points to the frequent 

 occurrence of suprarenal hypertrophy; together with Renon, he 

 discovered that hyperplasia of the suprarenals may be produced 

 by the repeated intraperitoneal injection of pituitary extract. 



Best known is the interrelationship between the hypophysis 

 and the sexual glands; the part played by the latter in the causa- 

 tion of acromegaly is as yet, however, undecided. The changes 

 in the sexual organs observed in acromegaly, and especially the 

 cessation of the menses in women, are among the earliest sym- 

 ptoms of the disease. Later on, there is cessation of sexual desire 

 and sterility, accompanied by atrophy of the genital glands. The 

 changes in the sexual glands in acromegaly have been minutely 

 described by Tandler and Gross. Not infrequently, the secondary 

 sexual characteristics disappear and there may be even a partial 

 return to the heterosexual type. Many authors (Freund, Ver- 

 straeten, Campbell, Breton and Michaud) believe that the changes 

 in the sexual glands are a causative factor in the production of 

 acromegaly. There is a certain amount of foundation for this 

 assumption, for it has long been known that the sexual glands 



