Retrograde labeling of central nervous pathways with tritiated or Evans blue-labeled bovine serum albumin

Neurosci Lett. 1976 Nov;3(4):191-6. doi: 10.1016/0304-3940(76)90072-0.

Abstract

In an attempt to develop a technique for the retrograde tracing of neuronal pathways which does not depend on enzyme activity of horseradish peroxidase (HRP), we have examined the retrograde transport of bovine serum albumin (BSA) by neurons of the central nervous system. Following injections of either tritiated or Evans blue-labeled BSA into the hippocampal formation of the rat, labeled neurons were found in the ipsilateral entorhinal area in a pattern which was highly reminiscent of that obtained with HRP. The retrograde transport of BSA provides a method for the retrograde tracing of central nervous pathways which is completely independent of the HRP method, making it possible to use both substances for studies of collateral innervation, and can be used with any fixative, or no fixative at all.