Observations on the functions of the liver : more especially with reference to the formation of the material known as amyloid substance, or animal dextrine, and the ultimate destination of this substance in the animal economy / by Robert M'Donnell.

  • McDonnell, Robert, 1828-1889.
Date:
1865
Catalogue details

Licence: Public Domain Mark

Credit: Observations on the functions of the liver : more especially with reference to the formation of the material known as amyloid substance, or animal dextrine, and the ultimate destination of this substance in the animal economy / by Robert M'Donnell. Source: Wellcome Collection.

    47/54 (page 35)
    a compouiul wliich, although in some respects resembling caseine, yet is not identical yvith. it. In order to obtain this material, the serum is to be diluted with ten times its bulk of distilled water, and on then adding, cautiously, very dilute acetic acid (one part of the glacial acid to fifty of distilled ■water), so as slightly to acidulate the whole, a white preci- pitate is formed, which slowly subsides. That this material is an azotised compound is shown by the characteristic odour emitted when it is burned on platinum foil, that it is not simply albumen is proved by its being precipitated and re- dissolved by agents (acetic acid, ammonia, &c.), wliich do not thus affect albumen, and by the fact, that when it is abstracted from a known quantity of serum, this still yields as much albumen as an equal quantity from which this material has not been taken away. It is probably the same substance which has been noticed by various authors, under different names, as existing in the blood.* It is to be found in the serum of all blood; but what I desire particularly to point out is, that it is much more abundant in the blood found leaving the liver during the period of digestion than in any other specimens of blood I have examined. Next to the blood of the hepatic veins, I have found the blood of the placenta richer in it than ordinary venous or arterial blood. It may be that the material in question has been confounded by Lehmann with the cell walls of the blood corpuscles of the hepatic veins, when he writes : But we may readily convince ourselves by the micro- scope of the almost entire absence of fibrine in the cruor of hepatic venous blood, and by the following experiment of the accuracy of this view, and of the great number of indestructible corpuscles in the blood of the hepatic veins. On mixing the fluid expressed from the clot with twenty times its quantity of water, porlal blood, like that of any other vein, yields a slight floc- culent deposit, in whichshreds of conglomerated cell-walls maybe • Nalalit Guillot and F. Leblanc: Note siir la presence de la caseine et Ifes variations de sea proportions dans le sang des hommes and des animaux. Compts Rend. t. xxxi. p. 585. Panum: Deber einem konstanten, mit dem Casein Ubcrreinstimmendcm Be»tandthed des Jilutcs Archiv fUr pathol. Anatomic von Vircbow nnd Ke.nhardt, iii Band, 2 heft, n. 251; also, Band iv. heft i. p 17 .»/^,/^«; >ote snr la presence clc ralbuminoso dans le sang, &e. Comnt. Kend, t. xxx. j>. 745. * '