Nitric oxide synthase expression after human brain contusion.

Caroline Gahm; Staffan Holmin; Tiit Mathiesen

doi:10.1097/00006123-200206000-00024

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PubMed · 12015851

Nitric oxide synthase expression after human brain contusion.

Caroline Gahm·Staffan Holmin·Tiit Mathiesen

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Abstract

OBJECTIVE: Nitric oxide is a universal mediator of biological effects in the brain, and it has been implicated in the pathophysiological processes of traumatic brain injury. Experimental studies have indicated posttraumatic up-regulation of the three different isoforms of nitric oxide synthase (NOS) (i.e., inducible NOS [iNOS], endothelial NOS, and neuronal NOS) after brain trauma. This study was undertaken to investigate the cellular sources and tissue compartments of nitric oxide produced by human patients undergoing surgical treatment for contusional brain injuries. METHODS: Contused brain tissue specimens from eight consecutive patients who underwent surgical treatment for brain contusions 3 hours to 5 days after trauma were evaluated in immunohistochemical analyses. Double-staining assays were used to define which cells produced the different isoforms. RESULTS: Increases in iNOS-positive cells were detectable within 6 hours after trauma, with a peak at 8 to 23 hours. Expression of iNOS after trauma was detected in neurons, macrophages, neutrophils, astrocytes, and oligodendrocytes. The cellular sources of iNOS differed at different times after trauma. No detectable difference in the expression of the neuronal or endothelial isoforms was observed for trauma patients, compared with control subjects. CONCLUSION: iNOS expression was up-regulated in a time-dependent manner in human brain tissue obtained from patients undergoing surgical treatment for contusional trauma. Our human data largely parallel experimental findings in rats, indicating that such trauma models are relevant for experimental studies and treatment trials.

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Adolescent Adult Brain Concussion Female Humans Immunohistochemistry Male Middle Aged Neurons Nitric Oxide Synthase Nitric Oxide Synthase Type I Nitric Oxide Synthase Type II Nitric Oxide Synthase Type III Reference Values Staining and Labeling Time Factors Journal Article Research Support, U.S. Gov't, P.H.S.

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Caroline Gahm, Staffan Holmin, Tiit Mathiesen. 2002. Nitric oxide synthase expression after human brain contusion.. https://doi.org/10.1097/00006123-200206000-00024

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