Abstract
Effects of 1-methyl-5-chloroindoline methylbromide (S-6) on Renshaw cells were investigated in cats anesthetized with pentobarbital sodium. S-6 proved to have little effect on spike discharges of Renshaw cells when administered intravenously, but the agent electrophoretically applied revealed excitatory effects which resembled the action of methacholine and such effects were blocked by intravenous administration of atropine. It was concluded that (1) S-6 is impermeant to the blood brain barrier and (2) the excitatory action of S-6 on Renshaw cells is muscarinic in nature.
