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PHOSPHATIDES OF THE LIVER. 385
acid, and oleic acid which is not identical with the ordinary oleic acid, also
linoleic acid and an acid having the formula C20H32O2. A part of
these unsaturated fatty acids are contained in the phosphatides but as
the unsaturated acids are about one-half of the fatty acids they must
also occur in the fats. The abundant occurrence of unsaturated fatty
acids is considered by the above-mentioned investigators as the first
step in the cleavage of the transportable fat from the fat tissues to the
liver and destined for use in the body. There is no doubt that the phos-
phatides are of great importance for this transformation of the fat.
Phosphatides, which were formerly designated lecithin, and whose
quantity is generally calculated as such, also belong to the normal con-
stituents of the liver. The quantity (as lecithin) amounts to over 23.5
p. m. according to Noel-Paton.1
In starvation the lecithin, according
bo Xoel-Paton, forms the greater part of the ethereal extract, while
with food rich in fat, on the contrary, it forms the smaller part. In
the liver of a healthy dog Baskoff 2
found 84 p. m. phosphatides (cal-
culated as lecithin) in the dry substance. The phosphatides are undoubt-
edly of various kinds, but they have not been closely studied. Among
others, Ave have lecithin and the so-called jecorin. Cholesterin is also a
constituent of the liver, although only in small quantities, and Kondo 3
finds that cholesterin ester occurs in the liver.
Jecorin was first found by Drechsel in the liver of horses, and also in the
liver of a dolphin, and later by Baldi in the liver and spleen of other animals, in
the muscles and blood of the horse, and in the human brain. It contains sul-
phur and phosphorus, but its constitution is not positively known. Jecorin dis-
solves in ether, but is precipitated from this solution by alcohol. It reduces
copper oxide, and gives a wine-red coloration with an ammoniacal silver-solution.
( hi boiling with alkali and then cooling it solidifies to a gelatinous mass. Manasse
has detected glucose as osazone in the carbohydrate complex of jecorin.
The statement by Bing that jecorin is a combination of lecithin and glucose
does not follow from the analyses of jecorin thus far known. Jecorin contains
sulphur, even as much as 2.75 per cent, and further the relation of P:N in lecithin is
1:1, while in jecorin it is quite different, 1: 2 to 1: 0. According to the investiga-
tions of Baskoff the liver jecorin, prepared according to Drechsel’s sugges-
tion, and when it is so pure that it is completely soluble in ether, and quantitatively
precipitated by alcohol from this solution, is a rather constant compound at
least in regard to the X, P and glucose content. Baskoff found as average 2.55
per cent X, 2.87 per cent P, and about 14 per cent glucose. The relation P:X
was nearly 1 :2 and therefore jecorin is correspondingly a diaminomonophosphatide.
The variable composition and divergent properties of the jecorin isolated and
analyzed by various investigators 4
depends, according to Baskoff, upon imper-
1
1. c. See also Heffter, Arch. f. exp. Path. u. Pharm., 28.
2
Zeitschr. f. physiol. Chem., 62.
3
Bioch. Zeitschr., 26.
* Drechsel, Ber. d. sachs. Gesellsch. d. Wissensch., 1886, p. 44, and Zeitsch. f. Biol-
ogie, 33; Baldi, Arch. f. (Anat. u.) Physiol., 1887, Suppl., 100; Manasse, Zeitschr. f.
physiol. Chem., 20; Bing, Centralbl. f. Physiol., 12, and Skand. Arch. f. Physiol., 9;
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