Levels of Batrachotoxin and Lack of Sensitivity to Its Action in Poison-Dart Frogs ( Phyllobates )
1980; American Association for the Advancement of Science; Volume: 208; Issue: 4450 Linguagem: Inglês
10.1126/science.6246586
ISSN1095-9203
AutoresJohn W. Daly, Charles W. Myers, Jordan E. Warnick, Edson X. Albuquerque,
Tópico(s)Neuroscience and Neural Engineering
ResumoBatrachotoxin is present in remarkably high amounts in the skin of Phyllobates terribilis . Levels of batrachotoxin tend to be reduced when P. terribilis is maintained in captivity, but even after being confined for up to 6 years, these frogs were still at least five times more toxic than other Phyllobates species used by natives for poisoning blowgun darts. Batrachotoxin was not detectable in F 1 progeny reared to maturity in captivity. Nerve and muscle preparations from wild-caught frogs and from the nontoxic F 1 frogs were both insensitive to batrachotoxin. The regulatory site controlling sodium-channel activation and permeability appears to have been minimally altered to prevent interaction with batrachotoxin, but is still sensitive to other sodium conductance activators (veratridine, grayanotoxin) to which the frogs are not exposed naturally.
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