Cytochrome c as a high resolution marker of neurons for light and electron microscopy.

Cytochrome c is taken up by lesioned neurons in the central and peripheral nervous system of the house fly. The enzyme reaction product is evenly distributed in cell bodies, axons, dendrites and axon terminals after 3-6 h uptake. No uptake into undamaged neurons, nor any transneuronal uptake could be demonstrated. Pre- and postsynaptic relations of cytochrome c-labeled neurons can be resolved.