THE INTERNAL SECRETION OF THE PANCREAS 459 



administration of suprarenal extract to these cases sometimes results bene- 

 ficially, but not so uniformly as does thyroid feeding in myxedema. 



Dreyer has given evidence that the products of this gland are discharged 

 into the blood of the adrenal vein in increased quantity on splanchnic 

 stimulation. 



This gland furnishes, on the whole, very conclusive evidence of the pres- 

 ence of an internal secretion that is absolutely necessary to the normal 

 metabolism of other organs. 



The Pituitary Body. This body is a small reddish-gray mass, occupying 

 the sella turcica of the sphenoid bone. 



It consists of two lobes, a small posterior one of nervous tissue, and an 

 anterior one resembling the thyroid in structure. The gland spaces of the 

 latter are oval, nearly round at the periphery, spherical toward the center 

 of the organ, and are filled with nucleated cells of various sizes and shapes 

 not unlike ganglion cells. 



The function of the pituitary body has not yet been fully established. 

 It has been supposed that the pituitary body has a function associated with 

 that of the thyroid. On the other hand, tumors or other disease of the 

 pituitary body have been found after death in association with a disease 

 known as acromegaly, in which the bones and soft parts undergo great 

 hypertrophy. 



Howell has found that extracts of the glandular lobe are inactive, but 

 that extracts of the infundibular lobe, when injected into the circulation, 

 produce marked rise of blood pressure, increase of vagus tonic inhibition, 

 and an augmentation of the heart's force. 



The Internal Secretion of the Pancreas. Minkowski and von 

 Mering have shown that total extirpation of the pancreas is followed in all 

 cases by the appearance of sugar in the urine in the course of a few hours. 

 The amount of sugar which appears is considerable, from 5 to 10 per cent. 

 This experimental disease is accompanied by an increase in the quantity of 

 urine and by abnormal thirst and appetite. It proves fatal in fifteen days or 

 less. These results are obtained only when the entire gland or more than 

 nine-tenths of it have been removed. If one-tenth or more of the gland be 

 left behind, sugar appears in the urine when carbohydrates are eaten, but not 

 otherwise. Nor is it necessary that the remaining portion of the gland be in 

 its normal situation. Successful grafts of pancreas under the skin of the 

 abdomen or elsewhere will prevent the appearance of sugar in the urine and 

 the other symptoms. If, however, the graft be subsequently removed, the 

 sugar in the urine and the other symptoms reappear, and the experimental 

 disease proceeds to a rapidly fatal issue. Opie and others have shown also 

 that in most cases of diabetes mellitus, there are pathological changes in the 

 islands of Langerhans. 



The symptoms produced by total extirpation of the pancreas do not de- 



