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since these vegetables contain starch, from which came the dextrin which he found in the liver.
(35.) The following results of experiments by Coze were read also at the session of Sept. 7th:*
(A) Under physiological conditions: 1st, the kind of death affects the quantity of sugar in the liver; the slower the death, the smaller being the quantity; 2d, the proportion of sugar in arterial blood is to that in the liver as 1:11. (B) Under pathological conditions: 1st, under the action of morphine hydrochlorate; (a) the sugar in the liver more than doubles, rising from 0:59 to 1:39; (6) the same is true of arterial blood, the amount increasing from 0.05 to 0·11 ; (c) the proportion of liver sugar to arterial sugar remains the same, 1:12, and hence pulmonary oxydation is not affected ; (d) the increase of sugar under the influence of
morphine is an argument against the employment of opium in treating diabetes, and explains the want of success met with in its use ; (e) no sugar is found in the urine. 2d, under the action of tartar-emetic; (a) the liver sugar remains unaltered ; (6) it is doubled in arterial blood, being 0:10 instead of 0.05; (c) the proportion between them is 1 : 6 instead of 1:11; (d) the combustion of sugar in the lungs is hindered,—thus accounting for the efficacy of this substance in pneumonia ;-(e) no sugar appears in the urine. The action of tartar-emetic upon the production and the destruction of glucose is precisely the reverse of the action of morphine.
(36.) In a paper communicated to the Academy Oct. 19th,t BONNET contends that the liver has a true glycogenic function, nothing analogous existing elsewhere in the animal economy; that the posthumous formation of sugar is established, the facts quoted to disprove it being inconclusive physiologically, since a liver-hash is not the normal liver ; that the two sugars of Figuier, one in the intestinal canal, the other in the portal vein, have no existence; that even if a non-fermentable sugar be admitted to exist in the portal blood, the fact remains that the liver in converting this into a fermentable sugar, exercises a true glycogenic function ; that the economy contains fatty, albuminoid and other matters, the elements of which by being differently grouped molecule by molecule, under certain unknown influences, may yield glycogenic matter; but that this result, performed outside the body by chemical action, does not represent a physiological fact; that any substance serving as a basis of Sanson's opinions may be in vain sought for in portal blood; that dextrin is transformed by fuming nitric acid directly into oxalic acid, without forming xyloidin ; that the formula of ordinary starch is not that of dextrin, anhydrous * C. R., xlv, 345.
+ Ib., p. 573.
starch and dextrin being €,,,,, while glycogenic matter is € 1,20.; that the latter resembles hydrated starch rather than dextrin, since like starch, it forms a paste with water and is colored blue by iodine, while dextrin does not form a paste and is not colored by iodine ; that glycogenic matter when isolated, does not resemble dextrin ; that Sanson is the only chemist who has found dextrin in the blood of the carnivora; that he (Bonnet) has not found it himself, and does not believe in its existence ; that dextrin, which is so easily transformed by ptyalin, cannot be taken as food and enter the system without change; that chopped meat does not contain sugar after exposure to the air ; that when food rich in sugar is taken, or when sugar is formed from starchy food by the diastase of the intestinal juices, it must be re-converted to dextrin, according to Sanson ; that no substance capable of producing this change is known; and that even admitting that dextrin exists in portal blood, its conversion into sugar by the liver is a true glycogenic function.
(37.) Moos published a paper in 1858,* in which he shows that when the pneumogastric nerves of healthy dogs who excrete 0.7 grams of liver sugar for each half kilogram of bodily weight are cut, this amount of sugar constantly diminishes, reaching even 0:1 gram, but never entirely disappears. rabbits, too, when this nerve is severed, the production of sugar is very slight. This result he ascribes partly to the important diminution in bodily weight and in all the secretions, including the formation of sugar, which takes place on dividing these nerves ; and partly to the diminished or altogether suspended nutrition. Electrical irritation of the spinal cord of frogs produces increased urination with diabetes, in a very short time. On ligating the vessels of the liver, though the amount of urine continues large, the sugar disappears. When the spinal cord of these animals is divided, the sugar formation is entirely arrested in the course of fifteen to twenty hours.
(38.) In a paper published at the same time, 7 KEKULÉ recommends Bernard's method as the most convenient one for the preparation of glycogen from the liver. A half-hour's boiling with strong potassic hydrate is sufficient to deprive it entirely of nitrogen. The ash, which consists of lime-salts, may be entirely removed by repeated solution either in strong acetic or in cold dilute nitric acid, and precipitation with alcohol. Kekulé confirms the views of Bernard, Hensen, and Pelouze relative to the properties of glycogen. It is white, and completely amorphous, and is colored violet or reddisha
* Verh. Med. Heidelberg, Jan., 1858; Jahresb., 1858, 568. + Ib.; Jahresb., p. 570.
brown by iodine. Its aqueous solution is opalescent, but becomes rapidly clear on boiling with dilute sulphuric acid ; though prolonged boiling is necessary to convert it into sugar. His analysis yielded the formula € 8, . Ꮎ The liver of dogs contained on an average two per
cent of glycogen. (39.) In a communication by POISSEUILLE and J. LEFORT to the Academy,t they state that in some physiological researches made by one of them, certain results were obtained, which were inexplicable except upon the assumption that glucose is destroyed in the lungs. But this is admitting the glycogenic hypothesis ; and since the radical objections made to it are enough to shake the strongest faith in it, they have undertaken, before giving their assent to it, to re-examine the whole subject ab ovo, seeking for glucose not only in the liver, but also in other organs of vertebrate animals. The livers of both fresh and salt water fish afforded, in some instances, from 0.484 to 1.5 per cent of sugar; but the intestines, spleens, roes, ovaries and muscles yielded none. In other cases, no sugar was detected anywhere. The liver of frogs gave 0-315 to 0:632 of sugar; the viscera and muscles none. the same result as fishes; the liver contained from 0 to 2.164 per cent of sugar, the viscera none. With mammals, the liver of hares gave none, of roe-deer 1.092, of three rabbits 1 to 1.163, of three cats 807 to 2:305, of two dormice in the hybernant state 0:624 per cent of sugar ; the other viscera and the muscular tissue gave none. Since sugar is destroyed when left in contact with decomposing animal matter, the authors infer that when a liver affords no sugar, it is because of such a change. They state that they have found sugar in the juice of the horse-flesh upon which their dogs were fed, as also in mutton, veal, beef and pork, though in minute quantity, a few milligrams for 100 grams of meat. The following experiments were made to ascertain the origin of this sugar : (A.) Dog, weight 33 kilos. fasting for 60 hours ; had been fed for a month with 3 to 4 kilos, horse-meat daily. The liver yielded 1.487 per cent glucose, the lymph of the thoracic duct 0.141, hepatic blood 0.821, portal, carotid, inferior vena caval blood, small intestines, mesenteric ganglions, none; blood of right ventricle, traces ; of left ventricle, lungs, spleen, kidneys, brain, urine, muscle, none. None of these fluids contained dextrin; the same is true of the organs, except the liver,—the decoction of which was slightly reddened by iodine,—and the muscles, in which the coloration was more decided. Without much doubt the portal blood, though it contains no sugar, yet contains a substance which is transformed into sugar; but it
C. R., xlvi, 565, March 22.
is in the liver that this change is effected. The sugar found in the lymph must come from the intestines or the liver ; but since the former contain none, it evidently must be taken up by the lymphatics from the liver-tissue. (D.) Horse in full digestion ; had eaten 10 liters of oats a day for the two previous days, and on the day of the experiment the same quantity at two different hours. The liver furnished 2.292, hepatic blood 1:128, chyle 0·222, lymph (from the vessels of the head and neck) 0:442, carotid blood 0.069, jugular blood above the ligature 0·050, portal blood above the ligature, 0·065, inferior vena cava below the ligature 0.057 per cent of sugar; mucus of the small intestine, the intestine itself, muscular tissue of the heart, locomotor muscles, traces ; pancreas, doubtful; mesenteric ganglions, spleen, kidneys, brain, lungs and urine, none; synovia from the knee joint 0·142 per cent. As before, sugar exists in the liver, in hepatic blood, and in the contents of the thoracic duct, but now also in arterial and portal blood, the intestinal walls, etc. Moreover, since the quantity of sugar found in the lymph in these experiments is 0.166
per cent for the dog, and 0.442 for the horse, while the quantity found in a lymphatic of the mesentery of a cow by the author of intestinal glycogeny is only 0.186 per cent, the conclusion is easily reached that it is the lymph and not the chyle which furnishes the sugar, and hence, that this is not produced in the intestine. To sum up, the liver of fishes, reptiles, birds and mammals, examined immediately after death, always contains sugar, while its presence in other organs is accidental and temporary, due to special physiological conditions ; consequently, " le foie seul forme du sucre.”
(40.) In a subsequent paper, these authors give some results, -obtained at Alfort-of'the examination of the intestinal chyle and the lymph of other parts of the body, of a bull killed while in full digestion. The chyle was collected from a large mesenteric vessel coming from the intestine; and 25 grams of lymph were obtained from a lymphatic vessel near the primitive carotid artery ; from this artery itself 300 grams of blood were taken. These liquids were prepared the same day and examined on the next. In the arterial blood 0.073 per cent of sugar was found ; in the chyle from the intestinal vessel, 0.123; in lymph taken from the neck, 0.266. The lymph, therefore, contains more sugar than the chyle; the reverse of this should be true, however, were glucose formed in the intestinal canal. It is clear, too, that during digestion all the sugar yielded by the liver is not destroyed in the lungs ; but that a portion passes into the arterial blood and thus into all the organs of the body; whence it is at length absorbed by the lymphatics, and poured, partly into the right subclavian vein directly, partly into the left subclavian by means of the thoracic duct. The lymphatics thus supply sugar to the superior vena cava, as the hepatic veins do to the inferior. In the carnivora, this action is temporary, taking place only during digestion ; in the herbivora, since they are always in digestion, it is permanent.
* C. R., xlvi, 677, Apr. 5, 1858.
(41.) In a report to the Paris Academy of Medicine upon the formation of glycogen in the animal organism,* POGGIALE states as the result of his experiments, that the preparation of glycogen-which in its properties stands between starch and dextrin-by means of glacial acetic acid, is to be preferred to any other method. As contained in a concentrated decoction of the liver, or in muscular juice, this substance, after gently heating with saliva, passes readily into fermentation, with the evolution of carbonic acid. With animals fed exclusively on meat, glycogen is found only in the liver. It exists abundantly in the liver of the herbivora, but occurs in other organs only when the food is rich in amylaceous matters.
(42.) Dr. F. W. Pavy, in a communication to the Royal Society, June 17, 1858,7 claims that the question under discussion is not whether sugar is found in the animal organism independently of saccharine food ; for this he is ready to grant. But it is whether the sugar thus found after death, is really present during life, or is the result of a post-mortem change. As early as Feb., 1854, he had noticed that scarcely a trace of sugar existed in blood removed by catheterizing the right ventricle during life. Sometime afterward, on repeating this experiment, his attention was fixed upon this point, and an investigation was undertaken to elucidate it. As the result of more than 60 observations, he now asserts that the condition of the blood after death cannot be taken as an indication of its state in life. He finds that in blood drawn from the right ventricle of an animal in a tranquil state, hardly a trace of sugar can be detected; while in blood collected from a fine incision in this organ immediately after death, sugar is present. In one experiment barely a trace existed in the blood during life, but nearly 1 per cent was found in that collected after death. It was natural to pass next to the organ in which, as is alleged, sugar is produced. As Bernard has shown that a substance readily convertible into sugar exists in the liver, it was necessary first to search for some substance which, when introduced into this organ, would check this post-mortem transformation. Potassic hydrate was found to answer this
* J. pharm., III, xxxiv, 99; Jahresb., 1858, 569. + Proc. Roy. Soc., ix, 300.