Venoms: Venomous Animals and Antivenomous Serum-therapeuticsCalmette, A. (Albert)
Science
Venoms: Venomous Animals and Antivenomous Serum-therapeutics
Calmette, A. (Albert)
Antitoxins; Poisonous snakes; Toxins; Venom
Delezenne, on his part, has established the existence in snake-venoms
of a _kinase_ analogous to the kinase of leucocytes and enterokinase.
Venom alone does not attack egg-albumen coagulated by heat, but it
confers an exceedingly strong digestive power on inert pancreatic
juices.
_Lachesis_-venom has been found to be much the richest in kinase. It
digests gelatine perfectly, and when this substance has been subjected
to its action it is no longer capable of being solidified.
_Lannoy_,[56] on the other hand, experimenting upon albuminoid
substances (casein, albumins of ox-serum) in solution, has shown
that _Cobra_-venom and that of _Vipera_ disintegrate the albuminoid
molecule; but the latter remains soluble after the addition of formol
and is no longer precipitable by acetic acid. The hydrolysis never
leads to the stage of peptone, but only to the formation of albumoses
which give biuret-reaction.
The action of venoms upon fibrin may be demonstrated _in vitro_
by bringing sufficient quantities of venom, 1 centigramme, for
example, into contact with small fragments of non-heated fibrin,
derived from blood clots from an ox, rabbit, or birds, and carefully
washed. These fragments soon separate from each other, and become
dissolved in a space of time which varies according to the venom used.
The VIPERINE-venoms, especially those of _Lachesis_ and
_Ancistrodon_, are the most active. _Viper_-venom is much less so, and
the venoms of COLUBRIDÆ are the slowest.
This proteolytic action of the various venoms corresponds pretty
exactly to their coagulant and decoagulant action on rabbit- or
horse-plasma, so that, as I have already stated, we must suppose that
the property possessed by VIPERINE-venoms of more or less
rapidly dissolving blood which they have caused to coagulate, results
from the fact that these venoms contain, in addition to a coagulant
substance, another substance which is strongly proteolytic.
The latter is destroyed by heating. _Lachesis_-venom, when heated to
70° C., no longer has any dissolving action on either gelatine or
fibrin. Moreover, antivenomous serum furnished by horses vaccinated
against heated venoms does not prevent proteolysis by non-heated
venoms. On the other hand, the serum of animals vaccinated against
VIPERINE-venoms, simply filtered by the Chamberland process
and non-heated, affords perfect protection to gelatine and fibrin
against the dissolving action of these venoms.
B.--CYTOLYTIC ACTION.
Simon Flexner and Noguchi[57] have observed that the venoms of
_Naja_, _Ancistrodon_, _Crotalus_, _Vipera russellii_, and _Lachesis
flavoviridis_, contain substances which possess the property of
dissolving a large number of the cells of warm-blooded and cold-blooded
animals, and that these _cytolysins_ are very markedly resistant to
high temperatures.
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