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FORM-ELEMENTS AND COAGULATION. 315
arr nol necessary for the contraction of the clot nor for the coagulation
ae a whole, and they are absent in the lymph and serous fluids. Accord-
ing to Petrone ’
they indeed have a function in retarding coagulation.
WoOLDBTOGl 2
takes a very peculiar position in regard to this question: he
considers the form-elements as only of secondary importance in coagulation.
Afl he has found, a peptone-plasma which has been freed from all form-con-
stituents by means of centrifugal force yields abundant fibrin when it is not
separated from a substance which precipitates on cooling. This substance,
which WOOLDRIDGE has called A-fibrinogen, seems to all appearances to be a
nucleoproteid. which, according to the unanimous view of several investigators,
originates from the form-elements of the blood, either the blood-plates or the
leucocytes and the generally accepted view as to the great importance of the
form-elements in the coagulation of the blood is not really contrary to Wool-
dridge’s experiments.
There is great diversity of opinion in regard to those bodies which
are eliminated from the form-elements of the blood before and during
coagulation.
According to Alex. Schmidt the leucocytes, like all cells, contain
two chief groups of constituents, one of which accelerates coagulation,
while the other retards or hinders it. The first may be extracted from the
cells by alcohol, while the other cannot be extracted. Blood-plasma
contains only traces of thrombin, according to Schmidt, but does con-
tain its antecedent, prothrombin. The bodies which accelerate coagu-
lation are neither thrombin nor prothrombin, but they act in this wise
in that they split off thrombin from the prothrombin. On this account
they are called zymoplastic substances by Alex. Schmidt. The nature
of these bodies is unknown, and Schmidt has given no opinion as to
their relation to the lime salts, which have been found to have zymoplastic
activity by other investigators.
The constituents of the cells which hinder coagulation and which are insoluble
in alcohol-ether are compound proteins, and have been called eytoglobin and
preglobidin by Schmidt. The retarding action of these bodies may be sup-,
pressed by the addition of zymoplastic substances, and the yield of fibrin on coagula-
tion in this case is much greater than in the absence of the compound protein
retarding coagulation. This last supplies the material from which the fibrin is
produced. The process is, according to Schmidt, as follows: The preglobulin
first splits, yielding serglobulin, then from this the fibrinogen is derived, and from
this latter the fibrin is produced. The object of the thrombin is two-fold. The
thrombin first splits the fibrinogen from the paraglobulin, and then converts the
»See footnote 2, p. 308. Also Schwalbe, ntcrs. z. Blutgerinnung, etc., Braun-
schweig, 1900; Morawitz, Deutsch. Arch. f. klin. Med.. 79, and Hofmeister’s Beitrage,
4 and 5; Biirker, Pflliger’s Arch., 102, and Centralbl. f. Physiol., 21; Deetjen, 1. c;
Le Sourd and Pagniez, Journ. de Physiol., 11; Vinci and Chistoni, Chem. Centralbl.,
1909, 2, 838, and Maly’s Jahresb., 39; Aynaud, Maly’s Jahresb., 39; 165; Petrone,
Mary’s Jahresber., 31, p. 170.
2
Die Gerinnung des Blutes (published by M. v. Frey, Leipzig, 1891).
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