Summary
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1.
Non-rectifying electrotonic coupling was found among neurons which receive inhibitory or biphasic synaptic input from the characterised dopamine neuron inPlanorbis corneus. No coupling was found among neurons receiving excitatory input.
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2.
There was wide variation in coupling between different neurons; coupling coefficients ranged from 0 to 0.5, and were not related to the proximity of the cell bodies.
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3.
Input from the dopamine neuron, or application of dopamine reduced the strength of coupling.
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4.
In some of the neurons the strength of coupling was increased by hyperpolarization; this appeared to result from the increase in input resistance with hyperpolarization shown by these particular neurons.
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5.
The coupled neurons could produce recurrent burst activity by two different mechanisms: by interactions within the network or as a result of endogenous pacemaker potentials.
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6.
Some of the implications of the coupling for analysis of data on transmission from the dopamine neuron are discussed.
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Part of this work was supported by a grant from the Medical Research Council to Dr. G.A. Cottrell.
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Berry, M.S., Pentreath, V.W. Electrotonic coupling among postsynaptic neurons of the characterised dopamine neuron inPlanorbis . J. Comp. Physiol. 131, 267–275 (1979). https://doi.org/10.1007/BF00610434
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DOI: https://doi.org/10.1007/BF00610434