PRODUCTION OF SUGAR IN THE LIVER. 



463 



FIG. 151.Cat?ieter for the 

 right side of the heart. 

 (Bernard.) 



E, extremity of the tube; 



E, stop-cock, e, extrem- 



ity to be introduced into 



the right auricle. 

 The tube is introduced 



through a small opening 



ugh 



into the external jugular 

 vein, the concavity of the 

 tube turned toward the 

 sternum, and the stop- 

 cock closed. When the 

 tube reaches the heart, 

 we feel the pulsations, 

 and the jet of blood, 

 when the stop-cock is 

 opened, is intermittent. 



0'-. 



the proof of the existence of sugar in the blood coming from the liver, Bernard demon- 

 strated its presence in blood taken from the right auricle in a living animal, which can 

 be readily done by introducing a catheter into the right side of the heart through 

 an opening in the external jugular 

 vein. He also showed that, during 

 digestion, the whole mass of blood 

 contained sugar, but that the quantity 



was greater in the right side of the ^ lilllliililillililiiP''- V 



heart than in the arterial system. 



It is unnecessary to cite all the 

 authorities that have confirmed the 

 observations of Bernard. Shortly 

 after these experiments were pub- 

 lished, Lehmann, Frerichs, and many 

 others verified their accuracy. Ber- 

 nard gives in full the experiments of 

 Poggiale and of Leconte, the results 

 of which were identical with his 

 own. He gives, also, in one of his 

 later works, the proportions of sugar 

 in the blood of the hepatic veins, ob- 

 tained by Lehmann, Schmidt, Pog- 

 giale, and Leconte, no sugar being 

 found in the blood of the portal sys- 

 tem. We have ourselves made a 

 number of experiments with a view 

 of harmonizing, if possible, the dis- 

 cordant observations of Bernard and 

 Pavy, and have examined the blood 

 from the hepatic veins for sugar, tak- 

 ing the specimens under what seemed 

 to be strictly physiological condi- 

 tions. In one of these published ex- 

 periments, blood was taken from the 

 hepatic veins of a large dog, fully- 

 grown and fed regularly every day 

 but not in digestion at the time of 

 the experiment, and the operation 

 lasted only seventy seconds. No 

 anesthetic was employed. The ex- 



T- 



tract of this specimen of blood, treat- 

 ed with Fehling's test-liquid, pre- 

 sented a well-marked deposit of the 

 oxide of copper, revealing unequivo- 

 cally the presence of a small quan- 

 tity of sugar. 1 This has been the in- 

 variable result in numerous experi- 

 ments and class-demonstrations made since 1858 ; and, since 

 the experiments just referred to were published, we have veri- 

 fied the observation with regard to the hepatic blood, keeping 

 the animal perfectly quiet before the operation, avoiding the 

 administration of an anaesthetic, and taking the blood so rap- 



1 FLINT, Jr., Experiments undertaken for the Purpose of reconciling some of the Discordant Observations 

 upon the Glycogenic Function of the Liver. New York Medical Journal, 1869, vol. viii., p. 381. These experi- 



FIG. 138. Double sound, used 

 for collecting blood from the 

 hepatic veins. (Bernard.) 



0, t, o', tube, with a stop-cock (r), 

 used to innate the rubber 

 bulb (G, b') ; O, T, tube, with 

 an opening (o'}, which re- 

 ceives the blood from the 

 hepatic veins, and is provided 

 with a stop-cock (K). 



