THE POISON OF EELS* BLOOD (ICHTHYOTOXINE). 241 



appear to be the most susceptible (lethal dose, according to 

 Mosso, 0-02 c.c. per kilo.), while the hedgehog is almost refrac- 

 tory. A. Mosso states that it has no action when introduced 

 into the stomach, though it is poisonous when injected into the 

 small intestine. On the other hand, a serious case of poisoning 

 in man after eating eels' blood is reported by PENNAVARIA. 1 

 Subcutaneous injection produces necroses and abscesses. The 

 course of the poisoning takes two distinct forms, according to the 

 dose. Rabbits die in convulsions a few minutes after receiving 

 Ol c.c. per kilo, of a very active serum, while sometimes there is 

 also a flow of saliva and blood into the urine. Myosis is hardly 

 ever absent, and sometimes exophthalmus occurs. 



The effects are attributed by Mosso to paralyses of the vagus, 

 preceded by stimulation. 



With small doses or weak poisons, however, conditions of 

 paralysis are produced, together with fine tremors, areas of local 

 anaesthesia, dyspnoea, flow of saliva, cries, &c., which, after 

 a great loss in weight, end in death, though only after some 

 hours, or even days (KOSSEL). 



Similar results have been observed with guinea-pigs. When 

 very large doses have been given death occurs so rapidly that 

 sometimes even the convulsions fail to appear. 



In the first case, therefore, the bulbar symptoms, especially 

 the rapid paralysis of the respiratory centre, predominate ; in 

 the second case, the spinal symptoms. The peripheral nerves 

 of the respiratory centre do not lose their capacity for being 

 stimulated. 



In the case of the frog A. Mosso was able to prove that the 

 excitability of the nerves and muscles rapidly decreased ; sensa- 

 tion, especially in the hind legs, disappeared before the power of 

 motion, probably through the destruction of the tracts from the 

 spinal cord to the brain. The isolated heart of a frog was not 

 affected. 



In warm-blooded animals the pressure of the blood rises im- 

 mediately after the injection, and then sinks. The action of the 

 heart slackens and becomes irregular, but the heart still con- 

 tinues to beat after death (BARDIER 2 ). After very large doses, 

 however, it was found by A. Mosso that the animal died very 

 rapidly from paralysis of the heart, while breathing still con- 

 tinued for a minute. The animals (dogs) also died from paralysis 



1 Pennavaria, Farmacista Italiano, xii., 328, 1888 (quoted by Robert, 

 loc. cit.). 



2 Bardier, "Action cardiaque du serum d'anguille," Soc. Biol., 1., 548, 

 1898. 



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