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FINDLAY E. RUSSELL
single toxin. Another characteristic of many marine venoms is their
relative instability. Some are very labile, even at temperatures down
to 0°C. While the marine toxins as a whole are far more varied in their
chemical composition than the venoms of terrestrial snakes or arthropods, there is some degree of consistency (or lack of consistency) within
a particular phylum, which is not unlike that seen in the terrestrial
venomous animals. The more simple marine forms have poisons
composed of one or several components having deleterious biological
effects ; the higher forms have poisons containing more components, and
in general these fractions appear to be more complex in structure and
function.
The zootoxicological properties of marine toxins vary as remarkably
as do their chemical properties. Some marine venoms provoke rather
simple effects, such as transient vasoconstriction or vasodilatation,
while others provoke more complex responses, such as parasympathetic
dysfunction or multiple concomitant changes in the blood-vascular
dynamics. The effects of the separate and combined activities of the
fractions of these poisons, and of the metabolites formed by their
interactions, is further complicated by the response of the envenomated
organism. The organism may produce and release several autopharmacologic substances which may not only complicate the poisoning but
which may in themselves produce more serious consequences than the
venom.
The zootoxicological study of marine poisons is further complicated
by the fact that qualitative as well as quantitative differences in the
chemical composition of these toxins may exist, not only from species
to species within the same genus, but from individual to individual
within the same species. A venom may even vary within the individual
animal at different times of the year or under different environmental
conditions. Thus, discrepancies in the proposed mode of action of a
toxin are likely to occur until our knowledge of the individual fractions
of these complex substances is more complete. In addition, obvious
difficulties in determining the chemical and zootoxicological properties
have arisen because of the differences in the methods of extracting
venom, the methods of storage (fresh, lyophilized or crystallized), and
the problems inherent in the methods of bioassay.
Most of our information on the zootoxicological properties of
marine toxins is based on studies with mammds, which, of course,
somewhat limits its application as far as understanding the design of
the toxin in the animals’ armament. The venom of the black widow
spider, for instance, did not evolve and adapt to the problems existing
between that spider and mammals. Thus, it is not surprising to fhd
FINDLAY E. RUSSELL
single toxin. Another characteristic of many marine venoms is their
relative instability. Some are very labile, even at temperatures down
to 0°C. While the marine toxins as a whole are far more varied in their
chemical composition than the venoms of terrestrial snakes or arthropods, there is some degree of consistency (or lack of consistency) within
a particular phylum, which is not unlike that seen in the terrestrial
venomous animals. The more simple marine forms have poisons
composed of one or several components having deleterious biological
effects ; the higher forms have poisons containing more components, and
in general these fractions appear to be more complex in structure and
function.
The zootoxicological properties of marine toxins vary as remarkably
as do their chemical properties. Some marine venoms provoke rather
simple effects, such as transient vasoconstriction or vasodilatation,
while others provoke more complex responses, such as parasympathetic
dysfunction or multiple concomitant changes in the blood-vascular
dynamics. The effects of the separate and combined activities of the
fractions of these poisons, and of the metabolites formed by their
interactions, is further complicated by the response of the envenomated
organism. The organism may produce and release several autopharmacologic substances which may not only complicate the poisoning but
which may in themselves produce more serious consequences than the
venom.
The zootoxicological study of marine poisons is further complicated
by the fact that qualitative as well as quantitative differences in the
chemical composition of these toxins may exist, not only from species
to species within the same genus, but from individual to individual
within the same species. A venom may even vary within the individual
animal at different times of the year or under different environmental
conditions. Thus, discrepancies in the proposed mode of action of a
toxin are likely to occur until our knowledge of the individual fractions
of these complex substances is more complete. In addition, obvious
difficulties in determining the chemical and zootoxicological properties
have arisen because of the differences in the methods of extracting
venom, the methods of storage (fresh, lyophilized or crystallized), and
the problems inherent in the methods of bioassay.
Most of our information on the zootoxicological properties of
marine toxins is based on studies with mammds, which, of course,
somewhat limits its application as far as understanding the design of
the toxin in the animals’ armament. The venom of the black widow
spider, for instance, did not evolve and adapt to the problems existing
between that spider and mammals. Thus, it is not surprising to fhd