PUNCTURE DIABETES. 927 



the condition of the liver which results from such puncture, and which 

 tends to cause this transformation of the glycogeii into sugar, is due to 

 a disturbance of the hepatic circulation, and especially of the circula- 

 tion in the hepatic artery, thus indirectly producing an alteration in the 

 normal metabolism of the organ ; but this cannot be considered as con- 

 clusively proved, and it may be due to a direct interference with the 

 action of the nerves to the liver cells. Diabetes does not, however, 

 occur on section of the splanchnic nerves alone. 1 But in all probability 

 the vasomotor centre is stimulated by the puncture, for other forms of 

 stimulation of the vasomotor centre also tend to produce a temporary 

 diabetes, such as the prolonged stimulation 2 of most sensory or afferent 

 nerves (e.g. the sciatic, the central end of the vagus, 3 and the depressor 4 ), 

 which are known so to influence the vasomotor centre as to produce 

 constriction or dilatation of the arteries of the body generally. It is 

 possible, therefore, that this may be the manner in which the effect is 

 produced in the liver, and that the glycaemia is due to the diminution 

 of the amount of oxygenated blood passing to the liver through the 

 hepatic artery, causing an excitation of the liver cells, and such conse- 

 quent alteration in their metabolic activity as ordinarily accompanies 

 excitation. 5 Many drugs produce temporary diabetes, e.g. acids, such as 

 phosphoric, lactic, and hydrochloric, also strychnine, curari, phosphorus, 

 arsenic, carbon monoxide. Some of these may act by affecting the 

 circulation, others by producing a dyspnoeic condition of the liver cells, 

 others again may be direct stimulants to the hepatic cells. 6 



It must be looked upon as a strong argument in favour of the glycogenetic 

 theory of Bernard, that we find as a concomitant of the altered (increased?) 

 activity of the hepatic cells, both after removal of the liver from the body, 

 and after the diabetic puncture, such an increased production of sugar in the 

 organ. It is certainly easier to explain the occurrence of puncture diabetes as 

 an excess of the normal production of sugar in the liver, than as a phenomenon 

 entirely sui generis. 



Action of the pancreas on carbohydrate metabolism. Until 

 recently, it was not known that the pancreas had any more influence 

 upon metabolism than other glands of the same type, such as the 

 salivary glands. There had, however, been isolated instances recorded 

 in which disease of the pancreas was accompanied by a condition of 

 diabetes ; but this, for the most part, was ascribed to the implication of 

 the sympathetic ganglia, which are in anatomical relationship to the 

 pancreas, and no special importance was attached to the pancreas in 

 connection with the symptom. 7 It was, however, shown in 1889, by 



1 According to Kaufmann (Compt. rend. Soc. de biol., Paris, 1894, p. 284), puncture 

 diabetes is not produced, if the nerves both to the pancreas and liver are cut ; but if one 

 set only is severed, it is found to occur. 



2 Even that produced by sections, Kiilz, Arch. f. d. yes. PhysioL, Bonn, 1881, Bd. xxiv. 

 S. 97. Here also will be found references to previous papers on the subject. 



3 Bernard, "Legons sur le systeme nerveux," Paris, 1858, tome ii. ; Eckhard, Beitr. 

 z. Anat. u. PhysioL (Eckhard), Giesen, Bd. viii. 



4 Filehne, Gentralbl. f. d. med. Wissensch., Berlin, 1878, No. 18. 



5 Cf. Araki, Ztschr. f. physiol. Chem., Strassburg, 1893, Bd. xvii. 



6 References to the literature of some of these substances will be given later ; others will 

 be found in Kiilz, loc. cit., supra ; and in Neumeister, "Lehrbuch," AuH. 2, S. 328. 



7 Since the discovery by v. Mering and Minkowski of the effects of total removal of the 



})ancreas, several cases of severe diabetes in man, associated with disease of that gland, 

 lave been recorded (G. Hoppe-Seyler, Deutsches Arch. f. Uin. Mcd., Leipzig, 1893, Bd. Hi. 

 S. 171 ; Buss, Diss., Gottingen, 1895). It must not be supposed, however, that this is at 

 all common. In most cases of diabetes no affection of the pancreas can be substantiated. 



