Actions of Acetylcholine on Spinal Motoneurons

  • Z. G. Jiang
  • N. J. Dun


The evidence that acetylcholine (ACh) is a chemical transmitter in the vertebrate peripheral nervous system is unequivocal. A transmitter and/or modulator role of ACh in the vertebrate central nervous system is less well established (cf. Karczmar, 1967; Krnjevic, 1974). The most extensively investigated central cholinergic synapses are those on Renshaw cells of the spinal cord where ACh was shown to be the excitatory transmitter released from collateral branches of spinal motoneurons (Eccles et al., 1954; 1956; Curtis and Eccles, 1958). The effect of ACh on the motoneuron itself is not well understood. Recent studies with antibodies raised against choline acetyltransferase (CAT) revealed in addition to CAT-containing motoneurons, the presence of CAT-containing small diameter neurons as well as fibers in the ventral horn (Kimura et al., 1981; Houser et al., 1983; Borges and Iversen, 1986). In fact, CAT-immunoreactive boutons appeared to abut on motoneurons suggesting that ACh may exert a transmitter and/or modulator role at these neurons (Borges and Iversen, 1986). In an effort to provide a pharmacological basis for a possible transmitter or modulator function of ACh in the ventral horn, the actions of ACh on motoneurons and on spinal synaptic transmission were investigated using thin spinal cord slices as stable intracellular recordings can be maintained for hours in this preparation.


Muscarinic Receptor Ventral Horn Membrane Resistance Excitatory Postsynaptic Potential Spinal Cord Slice 
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Copyright information

© Plenum Press, New York 1987

Authors and Affiliations

  • Z. G. Jiang
    • 1
  • N. J. Dun
    • 1
  1. 1.Department of PharmacologyLoyola University of Chicago, Stritch School of MedicineMaywoodUSA

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