MARINE TOXWS AND VENOMOUS AND POISONOUS MARINE ANIMALS
289
tryptamine. It was separable into 7 bands by polyacrylamide gel
electrophoresis.
When a mouse is stung by pedicellariae from a venomous sea
urchin it displays symptoms of respiratory distress and shows a significant fall in body temperature. The toxin has an inhibitory effect
on the oyster heart.
In 1952, Nigrelli named the toxic substance(s) of the Bahamian
sea cucumber, Actinopyga ugmsizi, holothurin. It is composed of 60%
glycosides and pigment, 30% salts, polypeptides and free amino acids,
5 to 10% insoluble protein and 1% cholesterol. A choleotrol-precipitated fraction known as holothurin A, which represents 40% of the crude
holothurin, has been given the empirical formula C50-52 H8l-85 0 2 5 - 2 6
S Na (Chanley et al., 1959). It appears to consist of at least four steroid
agly cones bound individually to four molecules of monosaccharides ; it
shows no absorption in the ultraviolet region. It is probably a mixture
of several related sulfate ester glycosides, each containing a steroid
aglycone of approximately 26-28 carbon and 4-5 oxygen atoms, one
molecule each of four different sugars and one molecule of sulphuric
acid as a sodium salt (Chanley et al., 1960). It resembles digitonin and
other saponins in both its chemical and biological activities. Holothurin
has a deleterious effect on some sharks and has been suggested as a
shark repellent.
In 10 parts per million, holothurin is lethal to Hydra, the mollusc
Planorbis, and the annelid Tubifex tubifex. It has slightly greater
hemolytic action than saponin, and stimulates hemopoiesis in the bone
marrow of winterized frogs. It also appears to have some antimetabolic
activity (Nigrelli and Jakowska, 1960). In the mammalian phrenic
nerve-diaphragm preparation, holothurin A produces a contracture of
the muscle, followed by some relaxation, and a gradual decrease in the
recorded amplitude of both the directly and indirectly elicited contractions, the latter decreasing at a slightly greater rate than the
former. The intravenous LD,, in mice is approximately 9 mg/kg body
weight (Friess et al., 1960). In experiments in frogs, Thron and his
colleagues (1963) have demonstrated that holothurin A produces an
irreversible block and destruction of excitability on the single node of
Ilanvier in the sciatic nerve. The toxin does not produce any observable
damage to the axonal walls or sheath. It is possible that the principal
deleterious neurotoxic effect is directed toward the nodal membrane.
The poison does not exert a blocking action on the in witro AChE-ACh
system.
Rio and associates (1963) have extracted a saponin-like substance from the sunburst starfish, Petasometra helianthoides A. H. Clark,
A.P.B.-3
P
289
tryptamine. It was separable into 7 bands by polyacrylamide gel
electrophoresis.
When a mouse is stung by pedicellariae from a venomous sea
urchin it displays symptoms of respiratory distress and shows a significant fall in body temperature. The toxin has an inhibitory effect
on the oyster heart.
In 1952, Nigrelli named the toxic substance(s) of the Bahamian
sea cucumber, Actinopyga ugmsizi, holothurin. It is composed of 60%
glycosides and pigment, 30% salts, polypeptides and free amino acids,
5 to 10% insoluble protein and 1% cholesterol. A choleotrol-precipitated fraction known as holothurin A, which represents 40% of the crude
holothurin, has been given the empirical formula C50-52 H8l-85 0 2 5 - 2 6
S Na (Chanley et al., 1959). It appears to consist of at least four steroid
agly cones bound individually to four molecules of monosaccharides ; it
shows no absorption in the ultraviolet region. It is probably a mixture
of several related sulfate ester glycosides, each containing a steroid
aglycone of approximately 26-28 carbon and 4-5 oxygen atoms, one
molecule each of four different sugars and one molecule of sulphuric
acid as a sodium salt (Chanley et al., 1960). It resembles digitonin and
other saponins in both its chemical and biological activities. Holothurin
has a deleterious effect on some sharks and has been suggested as a
shark repellent.
In 10 parts per million, holothurin is lethal to Hydra, the mollusc
Planorbis, and the annelid Tubifex tubifex. It has slightly greater
hemolytic action than saponin, and stimulates hemopoiesis in the bone
marrow of winterized frogs. It also appears to have some antimetabolic
activity (Nigrelli and Jakowska, 1960). In the mammalian phrenic
nerve-diaphragm preparation, holothurin A produces a contracture of
the muscle, followed by some relaxation, and a gradual decrease in the
recorded amplitude of both the directly and indirectly elicited contractions, the latter decreasing at a slightly greater rate than the
former. The intravenous LD,, in mice is approximately 9 mg/kg body
weight (Friess et al., 1960). In experiments in frogs, Thron and his
colleagues (1963) have demonstrated that holothurin A produces an
irreversible block and destruction of excitability on the single node of
Ilanvier in the sciatic nerve. The toxin does not produce any observable
damage to the axonal walls or sheath. It is possible that the principal
deleterious neurotoxic effect is directed toward the nodal membrane.
The poison does not exert a blocking action on the in witro AChE-ACh
system.
Rio and associates (1963) have extracted a saponin-like substance from the sunburst starfish, Petasometra helianthoides A. H. Clark,
A.P.B.-3
P