What is the mechanism of action of tetrodotoxin?
Tetrodotoxin is a sodium channel blocker. It inhibits the firing of action potentials in neurons by binding to the voltage-gated sodium channels in nerve cell membranes and blocking the passage of sodium ions (responsible for the rising phase of an action potential) into the neuron.
How is tetrodotoxin produced?
▼ Tetrodotoxin (TTX) is produced by a marine bacterium and accumulates in the tissues of a poisonous Pacific fish, the puffer fish. The puffer fish is regarded in Japan as a special delicacy, partly because of the mild tingling sensation that follows eating its flesh.
How does tetrodotoxin affect resting membrane potential?
Tetrodotoxin blocks the action potential and both the inward and outward transient current, but has no effect on either the resting membrane potential or the steady-state current.
How does tetrodotoxin affect the ion channel?
Abstract. Tetrodotoxin (TTX) is a potent toxin that specifically binds to voltage gated sodium channels. TTX binding physically blocks the flow of sodium ions through the channel, thereby preventing action potential (AP) generation and propagation.
What is the meaning of tetrodotoxin?
Definition of tetrodotoxin : a neurotoxin C11H17N3O8 found especially in puffer fish that blocks nerve conduction by suppressing permeability of the nerve fiber to sodium ions.
What is tetrodotoxin used for?
Because TTX blocks voltage-gated sodium channel and causes paralysis, it can also be applied as a potential pain relief and some researchers are trying to make use of the analgesic activity of TTX to treat various types of pains such as severe cancer pain [29,30,31], or to help in reducing cue-induced increases in …
What is the source of tetrodotoxin?
DESCRIPTION: Tetrodotoxin is an extremely potent poison (toxin) found mainly in the liver and sex organs (gonads) of some fish, such as puffer fish, globefish, and toadfish (order Tetraodontiformes) and in some amphibian, octopus, and shellfish species.
How does tetrodotoxin enter the body?
TTX can enter the body by injection, ingestion, inhalation, or via abraded skin. The oral LD50 (i.e. the median lethal dose in test organisms) in mice is 334 μg/kg; in a 75 kg human this would be equivalent to 0.765 mg, thus making TTX 10,000 times more poisonous than cyanide.
What is the effect of tetrodotoxin?
EFFECTS OF SHORT-TERM (LESS THAN 8-HOURS) EXPOSURE: Tetrodotoxin interferes with the transmission of signals from nerves to muscles by blocking sodium channels. This results in rapid weakening and paralysis of muscles, including those of the respiratory tract, which can lead to respiratory arrest and death.
What receptor does tetrodotoxin bind to?
voltage-gated sodium channels
Neurotoxin receptor site 1, in the outer vestibule of the conducting pore of voltage-gated sodium channels (VGSCs), was first functionally defined by its ability to bind the guanidinium-containing agents, tetrodotoxin (TTX) and saxitoxin (STX).
How many different elements are contained in tetrodotoxin?
The chemical structure of tetrodotoxin consists of 11 Carbon atoms, 17 Hydrogen atoms, 3 Nitrogen atoms, and 8 Oxygen atoms. When TTX enters the sodium channels of the human body, it binds to them and blocks the passage of sodium ions.
What color is tetrodotoxin?
Colorless crystalline solid that darkens when heated above 428°F (220°C).