Information AboutNeurotoxin |
| CATEGORIES ABOUT NEUROTOXIN | |
| neurotoxins | |
| peripheral membrane proteins | |
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A neurotoxin is a Toxin that acts specifically on nerve cells – Neuron s – usually by interacting with Membrane Protein s and Ion Channel s. Many of the Venoms and other toxins that organisms use in defense against Vertebrate s are neurotoxins. A common effect is paralysis, which sets in extremely rapidly. Examples of neurotoxins include Tetrodotoxin , Batrachotoxin and components of the venom in Bee s, Scorpion s, Spider s and Snake s. Toxins taken in from The Environment are described as ''exogenous'' and include Gas es (eg Carbon Monoxide ), metals (such as Mercury ), Liquid s ( Ethanol ) and an endless list of Solids . When exogenous toxins are taken in, the effect on neurons is largely dependent on dosage. Thus Ethanol (alcohol) is inebriating in low doses, only producing mild neurotoxicity. Prolonged exposure to "safe" alcohol levels slowly weakens and kills neurons. Neurotoxicity also occurs from substances produced within the body - ''endogenous'' neurotoxins. A prime example of a neurotoxin in the brain is Glutamate , which is paradoxically also a primary Neurotransmitter . When the glutamate concentration around a neuron reaches a critical point the neuron kills itself by a process called Apoptosis . This whole process is called Excitotoxicity , so named because glutamate normally acts as an excitatory neurotransmitter at lower levels. A potent neurotoxin such as Batrachotoxin affects the nervous system by causing Depolarization of nerve and muscle fibres due to increased Sodium Ion Permeability of the excitable Cell Membrane . SEE ALSO
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