Summary
Bath application ofl-glutamate, to larval dipteran muscle, at concentrations between 10−6 and 10−4 M will cause a depolarisation of the muscle membrane potential associated with an increase in muscle input resistance. At concentrations above 10−4 M there is usually a transient decrease in input resistance preceding the resistance increase.
l-aspartate at concentrations above 10−5 M causes membrane depolarisations which are always associated with an increase in muscle input resistance.
The pharmacology of the receptors regulating membrane depolarisations associated with increases in input resistance has been compared with the receptors gating synaptically activated cation channels and found to show significant differences in sensitivity to various ligands.
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Robinson, N.L. Anomalous resistance changes following application of the neurotransmitterl-Glutamate in insect muscle. J. Comp. Physiol. 148, 281–285 (1982). https://doi.org/10.1007/BF00619134
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DOI: https://doi.org/10.1007/BF00619134