billyaxon

I don't think there's really any reason an electrical synapse couldn't work... it could still trigger the same muscle cell depolarisation, calcium influx through voltage gated channels, and then muscle contraction as the ACh chemical synapse. It would occur faster, which might seem to give it an advantage over chemical transmission. But I think the chemical nature of the nmj synapse allows greater plasticity - the quantity of synapses from a single neuron can change more easily if it's not needed to join directly with the muscle cell - so the nervous system can grow to meet the demands of the muscles as they grow. This is just an idea, but it's about the only advantage of chemical synapses in this case that I could think of. Another major difference that might contribute, though I'm not sure how, is that electrical synapses allow current to travel both ways - the action of the muscle could perhaps trigger an action potential in the neuron going back to the cell body... whereas the chemical synapse is a one way thing.