Abstract
In addition to depolarizing the ventral horn cells including antidromically identified motoneurons in thin transverse neonatal rat spinal cord slice preparations, exogenously applied acetylcholine (ACh) suppressed the amplitude of excitatory postsynaptic potentials (EPSPs) either occurring spontaneously or elicited by stimulation of dorsal rootlets. A reduction of EPSPs could still be detected when the ACh-induced depolarization was nullified by hyperpolarizing current. Atropine but not d-tubocurarine effectively antagonized the depolarization and synaptic depression caused by ACh. While depressing the EPSPs, ACh had no appreciable effect on membrane depolarizations elicited by glutamate. Methacholine mimicked the depolarizing and synaptic depressant effects of ACh. The results suggest that muscarinic agonists inhibit synaptic transmission of ventral horn neurons including motoneurons by a presynaptic mechanism in reducing the output of excitatory transmitters.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 182-186 |
| Number of pages | 5 |
| Journal | Brain research |
| Volume | 381 |
| Issue number | 1 |
| DOIs | |
| State | Published - Aug 27 1986 |
| Externally published | Yes |
Keywords
- motoneuron
- muscarinic agonist
- presynaptic inhibition
- ventral horn neuron
ASJC Scopus subject areas
- General Neuroscience
- Molecular Biology
- Clinical Neurology
- Developmental Biology