Mixed synapses reconcile violations of the size principle in zebrafish spinal cord.

ABSTRACT: Mixed electrical-chemical synapses potentially complicate electrophysiological interpretations of neuronal excitability and connectivity. Here, we disentangle the impact of mixed synapses within the spinal locomotor circuitry of larval zebrafish. We demonstrate that soma size is not linked to input resistance for interneurons, contrary to the biophysical predictions of the 'size principle' for motor neurons. Next, we show that time constants are faster, excitatory currents stronger, and mixed potentials larger in lower resistance neurons, linking mixed synapse density to resting excitability. Using a computational model, we verify the impact of weighted electrical synapses on membrane properties, synaptic integration and the low-pass filtering and distribution of coupling potentials. We co

SUBMITTER: Menelaou E 

PROVIDER: S-EPMC9514842 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature