

DIABETES MEXL1TUS AND GLYCOSURIA. 265 



increased, grape-sugar appears in the Urine. In diabetes mellitus, grape-sugar 

 also appears in the urine, but this is really a serious disease, involving the 

 alteration of many tissues, and distinguished by profound disturbance of the whole 

 metabolic activity, which leads to numerous pathological changes and often to 

 death. The appearance of grape-sugar in urine does not necessarily mean that a 

 person is suffering from this disease.] 



The formation of large quantities of grape-sugar by the liver, and its passage 

 into the blood, and from the blood into the urine, constitute glycosuria. Extirpa- 

 tion of the liver in frogs, or destruction of the hepatic cells, as by fatty degeneration 

 from poisoning with phosphorus or arsenic, does not cause this condition. It occurs 

 for several hours, after the injury of a certain part the centre for the hepatic 

 vaso-motor nerves of the floor of the lower part of the fourth ventricle (CI. 

 Bernard's " piqure ") ; also after section of the vaso-motor channels in the spinal 

 cord, from above down as far as the exit of the nerves for the liver, viz., to the 

 lumbar region, and in the frog to the fourth vertebra (Schiff). When the vaso- 

 motor nerves, which proceed from this centre to the liver, are cut or paralysed in any 

 part of their course, mellituria or glycosuria is produced. All the nerve channels 

 do not run through the spinal cord alone. A number of vaso-motor nerves leave 

 the spinal cord higher up, pass into the sympathetic, and thus reach the liver ; so 

 that destruction of the superior (Pavy), as well as of the inferior cervical 

 sympathetic ganglion, and the first thoracic ganglion (EcJchard) of the abdominal 

 sympathetic, and often of the splanchnic itself produces it. The paralysis of the 

 blood-vessels causes the liver to contain much blood, and the intrahepatic blood- 

 stream is slowed. The disturbance of the circulation causes a great accumulation 

 of sugar in the liver, as the blood-ferment has time to act upon the glycogen and 

 transform it into sugar. By stimulation of the sympathetic at the lowest cervical 

 and first thoracic ganglion, the hepatic vessels at the periphery of the liver-lobules 

 become contracted and pale (Cyon). It is remarkable that glycosuria when 

 present may be set aside by section of the splanchnic nerves. This is explained 

 by supposing that the enormous dilatation and congestion, or the hyperemia of 

 the abdominal blood-vessels thereby produced, renders the liver anaemic. 



Continued stimulation of peripheral nerves may act reflexly upon the centre for the vaso- 

 motor nerves of the liver. Diabetes has been observed to occur after stimulation of the central 

 end of the vagus (CI. Bernard), and also after stimulation of the central end of the depressor 

 nerve (Filehne). Even section and subsequent stimulation of the central end of the sciatic 

 nerve causes diabetes. This may explain the occurrence of diabetes in people who suffer from 

 sciatica. [It may occur also after perverted nervous activity, as psychical excitement, neuralgias 

 (sciatica, trigeminal or occipital), concussion of the brain, as well as after certain injuries to the 

 skull and vertebral column and some cerebral diseases. ] 



According to Schiff, the stagnation of blood in other vascular regions of the body may 

 cause the ferment to accumulate in the blood to such an extent that diabetes occurs. The 

 glycosuria that occurs after compression of the aorta or portal vein may perhaps be ascribed to 

 this cause, but perhaps the pressure caused by these procedures may paralyse certain nerves. 

 According to Eckhard, injury to the vermiform process of the cerebellum of the rabbit causes 

 diabetes. In man, affections of the above-named nervous regions cause diabetes. 



[In most individuals the use of a large quantity of sugar in the food is not followed by the 

 appearance of sugar in the urine ; but in some exceptional cases it is often present, e.g., in 

 persons suffering from gastric catarrh, especially if they are gouty.] 



A number of poisons which paralyse the hepatic vaso-motor nerves produce diabetes ; curara 

 (when artificial respiration is not maintained), CO, amyl nitrite, ortho-nitro-propionic acid, and 

 methyl-delphinin ; less certainly morphia, chloral hydrate, HCN, and some other drugs ; 

 [phlorizin (v. Mering)] ; and some infectious diseases. But congestion of the liver produced in 

 other ways appears to cause diabetes, e.g., after mechanical stimulation of the liver. To this 

 class belongs the injection of dilute saline solutions into the blood (Bock, Hoffmann), whereby 

 either the change in form or the solution of the coloured blood-corpuscles causes the congestion. 

 The circumstance that repeated blood-letting makes the blood richer in sugar, may perhaps be 

 explained by the slowing of the circulation. 



[Most of the means which produce glycosuria in other animals fail to do so in birds ; even 

 the piqure rarely produces it. This Thiel and Minkowski attribute to the intensely active 



