Acetylcholine receptors on Renshaw cells of the rat.

Experiments have been performed on Renshaw cells of rats to investigate the receptors mediating both the responses to electrophoretically applied cholinergic excitants and the synaptic excitation following stimulation of the ventral roots. The effects of atropine and dihydro-beta-erythroidine, muscarinic and nicotinic antagonists respectively, have been tested on both types of excitation. Most importantly we found that in the rat the ventral root evoked response can be blocked by atropine as well as by DHbetaE. It was not possible to categorise the responses to the cholinergic agents in terms of muscarinic and nicotinic receptors. In addition we have failed the late (muscarinic) excitation seen in the cat.