The retrograde axonal transport of horseradish peroxidase (HRP), which was originally demonstrated in peripheral motorneurons, has aroused great interest among neuroanatomists. This technique has now become widely used as an experimental tool for demonstrating neuronal connections both in the central and in the peripheral nervous systems. A major advantage of the use of the enzyme HRP is elucidating the connections of the nervous system, that neuronal cell somata are labeled in a way, which enables the determination of the cells inducing a particular fiber pathway. The cells projecting to regions injected with HRP are identifiable with histochemical procedures because of the accumulation of vesicular packets of reaction product, which represents the pinocytotic incorporation of the protein at axon terminals. The intracellularly applied HRP is an invaluable marker for tracing neuronal projections to resolve the detailed morphology of individual neurons and for marking cells in synaptological analysis with the electron microscope.
ASJC Scopus subject areas
- Cell Biology