MAP2 and neurogranin as markers for dendritic lesions in CNS injury. An immunohistochemical study in the rat
Abstract:We compared two staining methods for the demonstration of dendrites under normal and pathological conditions of the rat central nervous system. MAP2- and neurogranin immunohistochemistry was applied to samples from normal tissue, spinal cord subjected to graded compression trauma, cerebral cortex following contusion trauma, and brains with focal ischemic lesions induced by occlusion of the middle cerebral artery (MCAO). Normal rats showed MAP2 immunoreactivity in nerve cell bodies and dendrites of brain and spinal cord. However, neurogranin staining was present only in nerve cell bodies and dendrites of the normal brain, and not in the spinal cord.
Reduction of MAP2 immunoreactivity was seen in lesions of spinal cords subjected to compression trauma. Neurogranin staining was of no value in this experimental condition since it was not present under normal conditions. The brain contusions showed loss of both MAP2- and neurogranin immunoreactivity at the site of the lesion. MCAO resulted in an extensive loss of MAP2- and neurogranin staining in the ipsilateral hemisphere.
In conclusion, our study shows that MAP2 immunostaining is a sensitive method for identifying dendritic lesions of various CNS injuries in the rat. Neurogranin immunostaining is an alternative method for investigations of dendritic pathology in the brain but not in the spinal cord.
Document Type: Original Article
Publication date: February 1, 2000