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Prof. E. A. Schafer. 



[July 22, 



Masay (1908) has endeavoured to produce " pituitary insufficience," 

 i.e. a diminution or interference with the functions of the gland, by 

 preparing an antiserum or cytotoxine by intraperitoneal injection of 

 a guinea-pig with an emulsion of dog's pituitary at intervals of two days, 

 and after five injections collecting the blood of the guinea-pig, centrifugalising 

 it, and injecting the serum (about 10 c.c.) under the skin of a dog. After 

 two or three such injections the dogs, according to Masay, show symptoms 

 which he interprets as due to pituitary insufficience, viz., loss of flesh, 

 muscular weakness, especially in hind limbs, and modifications in the 

 skeleton, accompanied by histological changes in the pituitary ; the symptoms 

 constituting, according to Masay, a veritable cachexia hypophysipriva. 

 But such experiments require to be multiplied and carefully controlled before 

 the results can be accepted as produced by changes in the pituitary body. 



Various views other than those here set forth have been taken regarding the functions 

 of the pituitary. Cvoq, who was one of the first to study the effects of intravenous 

 injections of pituitary extracts, considers that the gland secretes several active substances, 

 one of which in particular acts upon the regulator nerves of the heart — especially the 

 vagus — increasing the force of the beats and slowing the action of that organ, this being 

 accompanied by a raising of blood-pressure ; an action somewhat like that of muscarine. 

 Cyon also states that direct excitation of the gland in situ, whether electrical or 

 mechanical, is capable of producing effects of a similar character to intravenous injection. 

 According to Pirrone (1903) and to Livon (1908) these effects are not due to excitation of 

 the hypophysis but of adjacent parts of the brain or its membranes. But Cyon states 

 that after extirpation of the pituitary the effects are not got ; nor according to him is 

 a rise of blood-pressure obtained in the carotids on compressing the aorta in a hypophy- 

 sectomised animal. Masay (1908) has repeated these experiments and obtained results 

 similar to those of Cyon, but was inclined to attribute them to operative shock, although 

 recognising that this explanation offers difficulties. Cyon believes that the pituitary is 

 an organ which is closely inter-related to the thyroid, being set in activity by differences 

 of pressure within the skull, and influencing the flow of blood to the brain through the 

 thyroid. 



Eogowitz (1889) and others have regarded the pituitary as supplementary or vicarious 

 in its functions to the thyroid apparatus, this term including the parathyroids, but it is 

 difficult to reconcile this view with the results yielded by experiments on the effects of 

 extracts of the two glands and on the results of extirpation. 



An antitoxic function has also been ascribed to the organ, certain observers looking 

 upon the gland as destined to neutralise poisons of bacterial origin or even poisonous 

 substances produced by the tissues. This view was suggested, but apparently afterwards 

 relinquished by Marie, and has been upheld by Guerrini (1904), Gemelli (1906), and 

 Thaon (1907), who describe structural appearances in the pituitary after poisoning with 

 bacterial products and with certain drugs which they regard as evidences of a functional 

 reaction or hyperactivity. Such a conclusion does not, however, appear to be justified 

 by the facts observed. 



It seems, at any rate, clear that we must look upon the anterior lobe as 

 different in function from the posterior lobe (including the pars intermedia), 

 and it is advisable to study these parts as far as possible separately. 



