PHOSPHORYLATED NEUROFILAMENTS IN NEURONAL PERIKARYA AND DENDRITES IN HUMAN BRAIN FOLLOWING AXONAL DAMAGE

Experimental studies in animals have shown that neurofilament phosphor ylation, normally confined to axons, occurs aberrantly in neuronal per ikarya and dendrites following axonal damage. We have studied this phe nomenon in the human brain in cases of stroke and other focal lesions. Neurons with axons that project to damaged brain areas were found to show a Golgi-like staining of perikarya and dendrites upon immunostain ing with antibodies specific for phosphorylated epitopes of 200 kD neu rofilament protein. These results indicate that phosphorylation of neu rofilaments in perikarya is a component of the nonchromatolytic retrog rade reaction in at least some brain neurons whose axons have been inj ured. The strikingly detailed perikaryal and dendritic staining of the se neurons provides a new approach to the investigation of connections of specific morphological types of neurons in the human brain.