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. 1997 Aug 15;503(Pt 1):111–117. doi: 10.1111/j.1469-7793.1997.111bi.x

Aminergic modulation of glycine release in a spinal network controlling swimming in Xenopus laevis.

J R McDearmid 1, J F Scrymgeour-Wedderburn 1, K T Sillar 1
PMCID: PMC1159891  PMID: 9288679

Abstract

1. Neuromodulators can effect changes in neural network function by strengthening or weakening synapses between neurons via presynaptic control of transmitter release. We have examined the effects of two biogenic amines on inhibitory connections of a spinal rhythm generator in Xenopus tad poles. 2. Glycinergic inhibitory potentials occurring mid-cycle in motoneurons during swimming activity are reduced by 5-hydroxytryptamine (5-HT; serotonin) and enhanced by noradrenaline (NA). These opposing effects on inhibitory synaptic strength are mediated presynaptically where 5-HT decreases and NA increases the probability of glycine release from inhibitory terminals. 3. The amines also have contrasting effects on swimming: 5-HT increased motor burst durations while NA reduced swimming frequency. Aminergic modulation of glycinergic transmission may thus control fundamental parameters of swimming and force the spinal network to generate opposite extremes of its spectrum of possible outputs.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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