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. TTX has different binding affinities for different sodium channel isoforms. These differences are imparted by amino acid substitutions. Such substitutions confer TTX resistance to a variety of species. Tetrodotoxin resistance, however, may come at a cost to performance caused by changes in the biophysical properties and/or ion selectivity of the TTX resistant sodium channels. We here review the properties of sodium channels and their interaction with TTX, and look at some special examples of TTX resistant channels wherein the benefit of toxin resistance may be offset by other behavioral costs.

中文翻译：

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电压门控钠通道与神经毒素，河豚毒素之间的相互作用。

河豚毒素（TTX）是一种有效的毒素，可以特异性结合电压门控钠通道。TTX结合会物理阻止钠离子通过通道的流动，从而阻止动作电位（AP）的产生和传播。TTX对不同的钠通道同工型具有不同的结合亲和力。这些差异是由氨基酸取代引起的。此类取代使TTX对多种物种具有抗性。然而，由于对TTX抗性钠通道的生物物理性质和/或离子选择性的改变导致对河豚毒素的抗性以性能为代价。我们在这里回顾了钠通道的特性及其与TTX的相互作用，并观察了一些TTX抗性通道的特殊例子，其中抗毒素的益处可能会被其他行为成本所抵消。