Amphibian toxins

Tetrodotoxin (TTX) is a potent neurotoxin. Its name derives from Tetraodontiformes, an order that includes pufferfish, porcupinefish, ocean sunfish, and triggerfish; several of these species carry the toxin. Although tetrodotoxin was discovered in these fish, it is found in several other animals (e.g., in blue-ringed octopuses, rough-skinned newts, and moon snails). It is also produced by certain infectious or symbiotic bacteria like Pseudoalteromonas, Pseudomonas, and Vibrio as well as other species found in symbiotic relationships with animals and plants.

Batrachotoxin (BTX) is an extremely potent cardiotoxic and neurotoxic steroidal alkaloid found in certain species of beetles, birds, and frogs. The name is from the Greek word . Structurally-related chemical compounds are often referred to collectively as batrachotoxins. In certain frogs, this alkaloid is present mostly on the skin. Such frogs are among those used for poisoning darts. Batrachotoxin binds to and irreversibly opens the sodium channels of nerve cells and prevents them from closing, resulting in paralysis and death. No antidote is known.

Bufotenin, also known as dimethylserotonin or as '5-hydroxy-N,N-dimethyltryptamine (5-HO-DMT'), is a serotonergic psychedelic of the tryptamine family. It is a derivative of the psychedelic dimethyltryptamine (DMT) and of the neurotransmitter serotonin (5-hydroxytryptamine; 5-HT). The compound is an alkaloid found in some species of mushrooms, plants, and toads. It is also found naturally in the human body in small amounts. Bufotenin, for instance derived from the trees Anadenanthera colubrina and Anadenanthera peregrina, has a long history of entheogenic use as a snuff in South America.

Bufotoxins are a family of toxic steroid lactones or substituted tryptamines of which some are toxic. They occur in the parotoid glands, skin, and poison of many toads (Bufonidae family) and other amphibians, and in some plants and mushrooms. The exact composition varies greatly with the specific source of the toxin.

Epibatidine is a chlorinated alkaloid that is secreted by the Ecuadorian frog Epipedobates anthonyi and poison dart frogs from the genus Ameerega. It was discovered by John W. Daly in 1974, but its structure was not fully elucidated until 1992. Whether epibatidine occurs naturally remains controversial due to challenges in conclusively identifying the compound from the limited samples collected by Daly. By the time that high-resolution spectrometry was used in 1991, there remained less than one milligram of extract from Daly's samples, raising concerns about possible contamination. Samples fro

Samandarin or Samandarine is the main steroidal alkaloid secreted by the fire salamander (Salamandra salamandra). The compound is extremely toxic (LD50 = 70 μg/kg in mice). Poisoning can cause convulsions, respiratory paralysis, and eventual death. Samandarin is also believed to be the active ingredient in Salamander brandy, a Slovenian traditional medicinal alcoholic drink with purported hallucinogenic and aphrodisiac effects.

Bufotalin is a cardiotoxic bufanolide steroid, cardiac glycoside analogue, secreted by a number of toad species. Bufotalin can be extracted from the skin parotoid glands of several types of toad.

thumb|right|Histrionicotoxin 283A

chemical compound

Marinobufagenin (marinobufagin, MBG) is a cardiotonic bufadienolide steroid. It is secreted by the toad species such as Bufo marinus. It also can be found in the plasma and urine of human subjects with myocardial infarction, kidney failure, heart failure, and preeclampsia. MBG is a vasoconstrictor and a sodium–potassium adenosine triphosphatase (Na/K-ATPase) inhibitor with a high affinity for the alpha-1 isoform of the enzyme, the main isoform in the vascular wall and the kidney.

Bufothionine is a sulfur-containing compound which is present in the bufotoxins secreted by the parotoid gland of certain toads of the genera Bufo and Chaunus. The structure has been shown by X-ray crystallography to be (1,3,4,5-tetrahydro-5,5-dimethylpyrrolo-[4,3,2-de]quinolinio)-6-sulfate. This specific compound can be found in the skin of certain species of toad such as the Asiatic Toad, Chaunus arunco, Chaunus crucifer, Chaunus spinulosus, and Chaunus arenarum.

Samandaridine is an extremely toxic alkaloid produced by the skin glands of various salamanders.

chemical compound

Dermaseptins are a family of peptides isolated from skin of the frog genus Phyllomedusa. The sequence of the dermaseptins varies greatly but due to the presence of lysine residues all are cationic and most have the potential to form amphipathic helices in water or when integrated with the lipid bilayer of the bacterial membrane. Clear separation of two lobes of positive and negative intramolecular electrostatic potential is thought to be important in cytotoxic activity. Dermaseptins are typically 27-34 amino acid residues in length and were the first vertebrate peptides demonstrated as having