Effects of mecamylamine on the Golgi recurrent collateral--Renshaw-cell synapse in the spinal cord

The fact that mecamylamine is a secondary amine with "nicotinic" blocking properties suggested it would act at the Golgi recurrent collateral--Renshaw-cell synapse in the spinal cord. Glass micropipettes were used to obtain extracellular Renshaw-cell discharges due to antidromic ventral root stimulation in cats anesthetized with pentobarbital. The effects of mecamylamine, hexamethonium, physostigmine, and nicotine given intravenously were determined in this preparation. It was found that mecamylamine reduced the terminal portions of the repetitive discharge of Renshaw cells to antidromic stimulation. The stimulant effect of physostigmine and nicotine on Renshaw cells was blocked by mecamylamine. Hexamethonium in similarly effective ganglionic blocking doses had no effect.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/32383/1/0000458.pd