Poisons that have an action against neurons (see NEURON) are known as neurotoxins. Some are tools used in neuroscience to make a LESION in neural tissue while others (such as CONOTOXINS) occur naturally and are used by predators to capture prey. Many substances can destroy neurons non-selectively—copper sulphate for example—while other chemicals have more specific effects on tissue.
EXCITOTOXINS act at GLUTAMATE RECEPTORS and destroy cell bodies but not other local tissue elements; GLIOTOXINS destroy GLIAL CELLS. Still other neurotoxins have effects against chemically identified neurons: 6-HYDROXYDOPAMINE destroys CATECHOLAMINE containing neurons while 5,7-DIHYDROXYTRYPTAMINE destroys those containing SEROTONIN. MPTP (l-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) is an extremely selective and species specific neurotoxin with actions on the DOPAMINE containing neurons of the SUBSTANTIA NIGRA of PRIMATES. In using neurotoxins, the goal of neuroscientists is to make lesions as selective for a particular type of neuron as possible: IMMUNOTOXINS offer the possibility of being able to generate highly selective lesions.
