the chemical and evolutionary ecology of tetrodotoxin (ttx) toxicity in terrestrial vertebrates河豚毒素(ttx)的化学和进化生态学陆栖脊椎动物的毒性.pdf

Mar. Drugs 2010, 8, 577-593; doi:10.3390/md8030577 OPEN ACCESS Marine Drugs ISSN 1660-3397 /journal/marinedrugs Review The Chemical and Evolutionary Ecology of Tetrodotoxin (TTX) Toxicity in Terrestrial Vertebrates Charles T. Hanifin Hopkins Marine Station of Stanford University, 120 Oceanview Blvd. Pacific Grove CA, 93950, USA; E-Mail: charlesh@; Tel.: +01-1-831-655-6220 Received: 24 February 2010; in revised form: 3 March 2010 / Accepted: 8 March 2010 / Published: 10 March 2010 Abstract: Tetrodotoxin (TTX) is widely distributed in marine taxa, however in terrestrial taxa it is limited to a single class of vertebrates (Amphibia). Tetrodotoxin present in the skin and eggs of TTX-bearing amphibians primarily serves as an antipredator defense and these taxa have provided excellent models for the study of the evolution and chemical ecology of TTX toxicity. The origin of TTX present in terrestrial vertebrates is controversial. In marine organisms the accepted hypothesis is that the TTX present in metazoans results from either dietary uptake of bacterially produced TTX or symbiosis with TTX producing bacteria, but this hypothesis may not be applicable to TTX-bearing amphibians. Here I review the taxonomic distribution and evolutionary ecology of TTX in amphibians with some attention to the origin of TTX present in these taxa. Keywords: tetrodotoxin; TTX; Amphibia; Caudata; Anura; Salamandridae; Taricha;