REACTIVE ASTROCYTES EXPRESS NITRIC-OXIDE SYNTHASE IN THE SPINAL-CORD OF TRANSGENIC MICE EXPRESSING A HUMAN CU ZN SOD MUTATION/

THE distribution of the neuronal isoform of nitric oxide synthase (nNO S) in the spinal cord of transgenic mice expressing a mutated human co pper/zinc superoxide dismutase gene was enhanced when investigated by immunocytochemistry. Immunocytochemistry showed intensely stained NOS- immunoreactive (IR) glial cells with the appearance of astrocytes in t he spinal cord and brain stem of transgenic mice, but none were observ ed at these sites in control mice. Using antisera directed against GFA P, the specific marker for astrocyte, the glial cells were confirmed b y immunocytochemistry to be astrocytes. This immunocytochemical eviden ce suggests that nitric oxide may mediate glutamate neurotoxicity, and this study provides the first in vivo evidence that nitric oxide may be implicated in the pathologic process of human familial amyotrophic lateral sclerosis. (C) 1998 Rapid Science Ltd.