Chemical pathology : being a discussion of general pathology from the standpoint of the chemical processes involved / by H. Gideon Wells.

  • Wells, H. Gideon (Harry Gideon), 1875-1943.
Date:
1918
Catalogue details

Licence: In copyright

Credit: Chemical pathology : being a discussion of general pathology from the standpoint of the chemical processes involved / by H. Gideon Wells. Source: Wellcome Collection.

    83/734 (page 77)
    sugar combustion that is normally accomplished. 0. Cohnheim 13a at- tempted to explain the failures by his observation that the pancreas produces a substance that activates an inactive glycolytic enzyme in the muscles, liver, and probably in other organs. This work has been much contested, and is not generally accepted, so we are still in the dark as to how the carbohydrate oxidations are accomplished. (See Chapter xxii.) LIPASE 14 Lipase is probably present in greater or less amount in all cells. In the discussion of the reversible action of enzymes, on a previous page, the modem conception of fat metabolism has been explained, which considers it to depend upon the existence of lipase in the cells and fluids throughout the body. On account of the technical diffi- culties in the way of using higher fats, such as triolein, in experi- mental work, the esters of lower fatty acids have generally been used, particularly ethyl butyrate, salicylic acid esters, and glycerol triace- tate. Enzymes splitting ethyl butyrate, and presumably higher fats, have been demonstrated in practically all tissues examined; the names of Kastle and Loevenhart in this country, and Hanriot in France, being particularly connected with this work. Whether in all cases the presence of this reaction is proof positive of the presence of an enzyme splitting fats, a true “lipase,” is not yet known. Much of the work so far reported on the occurrence of lipase in tissues is of questionable value, especially as to quantitative results, because of faulty methods. Saxl15 points out and avoids some of these errors, and finds that during autolysis of tissues the splitting of the natural fats present in the cells is but slight; simple esters are attacked more, especially amyl-salicylate; muscle and blood are the least active tissues. Most authors agree that lymphoid cells are especially rich in lipolytic enzymes.17 In the serum of normal individuals the esterase content seems to be quite constant,15a and Quinan 15b found the tissue content also constant, the liver containing about twice as much as the kidney and over three times as much as the muscle. He states that different parts of the brain have characteristic lipase activity (butyrase).15c Thiele15d has found that blood, chyle, and various tissues also contain an enzyme which can hydrolyze lecithin, but except i3a Zeit. physiol. Chem., 1903 (39), 336; also see Simpson, Biochem. Jour., 1910 (5), 126. i4 For literature on lipase see Connstein, Ergebnisse Physiol., 1904 (3, Abt. 1), 194; concerning the behavior of lipase see Taylor, Jour. Biol. Chem., 1906 (2), 103; Falk, Proc. Natl. Acad., 1915 (1), 136. is Biochem. Zeit., 1908 (12), 343. 17 The distribution of lipases in different species of animals and their various organs has been investigated bv Porter, Miinch. med. Woch., 1914 (61), 1774. !5a Sagal, Jour. Med. Res., 1916 (34), 231. isb Ibid., 1915 (32), 45. i5c Ibid., 1916 (35), 79. isd Biochem. Jour., 1913 (7), 275.