Chol-1: A cholinergic-specific Gganglioside of possible significance in central nervous system neurochemistry and neuropathology

By use of an antiserum raised against presynaptic plasma membrane purified from the purely cholinergic electromotor system of Torpedo marmorata we have been able to identify a group of antigenically-related minor gangliosides (collectively designated Chol-1) that appear to be exclusively localized on cholinergic neurons. The cholinergic-specificity of these antigens has been shown by the following findings a) The anti-Choi-1 antiserum induces a selective complement-mediated lysis of the cholinergic subpopulation of mammalian brain synaptosomes; b) Section of the fimbria, which causes a massive degeneration of cholinergic terminals in the hippocampus, leads to a concomitant depletion of the level of the Chol-1 gangliosides in the hippocampus; c) The anti-Choi-1 serum can be used to immunostain cholinergic elements in the central and peripheral nervous systems of the rat. The discovery of a cell surface cholinergic-specific antigen has provided a new and effective tool with which to study the cholinergic neuron. For instance, we have immuno-isolated cholinergic synaptosomes from rat cortex and used this preparation to study transmitter coexistence. Our results indicate that approximately 75% of the cortical cholinergic neurons also express the neuropeptide VIP. Furthermore, we are investigating the expression of Chol-1 in patients affected by diseases such as ALS which primarily involve central cholinergic neurons.