The composition of the venom differs greatly between species and between individual snails within each species, each optimally evolved to paralyse it's prey. The active components of the venom are small peptides toxins, typically 12-30 amino acid residues in length and are highly constrained peptides due to their high density of disulphide bonds. The venoms consist of a large number of different peptide components that when separated exhibit a range of biological activities : when injected into mice they elicit a range of physiological responses from shaking to depression! The paralytic components of the venom that have been the focus of recent investigation are the alpha, omega and mu conotoxins. All of these conotoxins act by preventing neuronal communication, but each targets a different aspect of the process to achieve this.The alpha-conotoxins target nicotinic ligand gated channels, the mu-conotoxins target the voltage-gated sodium channels and the omega conotoxins target the voltage-gated calcium channels. Introduction to neurochemistry
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