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CHOLINE. 247
which may be considered as the anhydride of the arid corresponding to
choline. Muscarine and betaine can he obtained from choline on oxida-
tion. Choline yields trimethylamine as a decomposition product, and this
seems to be formed in the transformation of choline in the animal body.
( holine occurs in the plant kingdom as well as in the animal kingdom.
Mott and Halliburton have repeatedly found choline in the blood in
degenerative diseases of the nervous system. It was first shown also in
normal blood by Marino Zuco, l
and this investigator first found it in
tbe suprarenal capsule, but designated it neurine. Lohmann found it
later in this organ, and recently it has been found in various organs by
other investigators, especially by C. Schwarz and v. Furth. The fact
that choline is a cleavage product of lecithin in the animal, and that it is
antagonistic to adrenalin (of the suprarenal capsule) by its depressing
action upon the blood pressure, and that it has an exciting action upon
certain secretions (Lohmann, Theissier and Thevenot, v. Furth
and Schwarz 2
), gives choline great physiological importance. The
physiological action of choline is still very much disputed.
Choline is a syrupy fluid, readily miscible with absolute alcohol.
Hydrochloric acid gives with it a compound which is very soluble in water
and alcohol, but insoluble in ether, chloroform, and benzene. This com-
pound forms a double combination with platinum chloride, is soluble in
water, insoluble in absolute alcohol and ether, and crystallizing from
water in monoclinic system and this form is strongly double-refractive.
From a mixture of water and alcohol it crystallizes in the regular form
(octahedral). Both forms can be changed from one to the other
and are used according to Kauffmann and Vorlander 3
in the detec-
tion of choline. Choline also forms a crystalline double compound
with mercuric chloride and with gold chloride. Choline is precipitated
by potassium iodide and iodine (Gulewitsch), and potassium triiodide
can be used for the quantitative estimation of this base (Stanek 4
).
On heating the free base it decomposes into trimethylamine, ethylene
oxide, and water.
In preparing choline from lecithins, and also for the detection of
lecithin in an alcohol-ether extract, proceed as follows: The residue from
1
Mott and Halliburton, Philos. Trans., Ser. B, 191 (1899) and 194 (1901); Marino
Zuco, see Maly’s Jahresber., 24, pp. 181 and 698.
2
Lohmann, Pfluger’s Arch., 118 and 122; v. Furth and Schwarz, ibid., 124, which
also contains the literature.
3
See Gulewitsch, Zeitschr. f. physiol. Chem., 24; Kauffmann and Vorlander, Ber.
d. d. chem. Gesellsch., 43.
4
Gulewitsch, Zeitschr. f. physiol. Chem., 24; Stanek, ibid., 56. In regard to the
quantitative estimation see also Kiesel, ibid., 53; Stanek, ibid., 54; Moruzzi, ibid.,
55; and MacLean, ibid., 55.
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