title: Lysyl oxidase, the extracellular matrix-forming enzyme, in rat brain injury sites.
abstract: Lysyl oxidase is an extracellular enzyme that catalyzes cross-linkages of extracellular matrix proteins. We hypothesized that this enzyme is secreted by cells attracted to central nervous system injury sites and is involved in extracellular matrix modulation and in scar formation. Specific antibodies for immunohistochemistry and enzyme activity measurements were used to detect the presence of lysyl oxidase after longitudinal knife cuts in adult rat forebrain. Immunoreactivity was observed within the core of injury sites from 1 and up to 30 days postoperative, with less staining at 2 and 5 days, and was not associated with glial fibrillary acidic protein-positive astrocytes. Enzyme activity increased transiently in injury site regions with a peak (200% of control) at 10 days postoperative. These results are the first to provide evidence for a time-dependent appearance of active extracellular lysyl oxidase in brain injury sites. They imply that enzyme molecules are synthesized and secreted by cells attracted to brain injury sites and participate in extracellular matrix modulation.
authors.affiliation: Assaf Harofeh Medical Center, Laboratory of Neuroscience, Research and Development, P.O. Beer Yaakov, 70300, Zrifin, Israel. gmgilad@asaf.health.gov.il
authors.forename: G M
authors.initials: GM
authors.lastname: Gilad
authors.forename: H M
authors.initials: HM
authors.lastname: Kagan
authors.forename: V H
authors.initials: VH
authors.lastname: Gilad
mesh_terms: D000818:Animals; D001930:Brain Injuries / Q000201:enzymology* / Q000473:pathology; D002831:Choroid Plexus / Q000033:anatomy & histology / Q000473:pathology / Q000502:physiology; D005109:Extracellular Matrix / Q000201:enzymology*; D016326:Extracellular Matrix Proteins / Q000096:biosynthesis*; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D006499:Hepatic Artery / Q000473:pathology / Q000502:physiology; D007150:Immunohistochemistry; D008297:Male; D009416:Nerve Regeneration / Q000502:physiology; D008249:Protein-Lysine 6-Oxidase / Q000378:metabolism*; D051381:Rats; D014951:Wounds, Stab / Q000201:enzymology
chemical_list: D016326:Extracellular Matrix Proteins; D005904:Glial Fibrillary Acidic Protein; D008249:Protein-Lysine 6-Oxidase