Neuronal mapping: a photooxidation reaction makes Lucifer yellow useful for electron microscopy

Abstract

Irradiation Lucifer yellow-filled neurons with intense blue light in the presence of 3,3'-diaminobenzidine produces an electron-opaque osmiophilic polymer within the injected cells. This technique is valuable when cobalt or horseradish peroxidase injections are difficult or when a second intracellular marker is needed to demonstrate neuronal contacts.