Effect of denervation on a cholinergic-specific ganglioside antigen (Chol-1) present in Torpedo electromotor presynaptic plasma membranes.

The presence of Chol-1, an antigen identified in the plasma membrane of cholinergic electromotor nerve terminals of Torpedo marmorata, was investigated in Torpedo electric organ after 3, 6, and 9 weeks' denervation. Denervation was monitored by the cessation of stimulus-evoked discharge potentials, by the reduction in nerve terminals seen morphologically, and by the decrease in ACh and ChAT contents. The content of ganglioside-bound sialic acid did not show any appreciable change with time. Some modification of ganglioside pattern on TLC was observed after 9 weeks' denervation. The presence of Chol-1 after denervation was assayed by its activity in inhibiting the selective complement-induced lysis of the cholinergic subpopulation of guinea pig cortical synaptosome which is mediated by the anti-Chol-1 antiserum. Denervation did not affect Chol-1 immunoreactivity although it did alter the distribution of the immunoreactivity among gangliosides. The possible significance of the results is discussed.