3-D Golgi and image analysis of the olfactory tubercle in schizophrenia

To examine morphologic changes in the olfactory tubercle (OT) spiny neurons and astrocytes in schizophrenia (Sch) by means of quantitative 3-D Golgi and immunocytochemical studies.

Free-floating vibrotome sections of postmortem brain tissue from 10 controls and 12 Sch cases were used for Golgi study and glial fibrillary acidic protein (GFAP) immunocytochemistry. A gray level image analysis was applied for quantitative estimation of GFAP-positive astrocytes on uniform, randomly sampled sections. This method is effective for low-contrast objects on an uneven background. Golgi-impregnated OT spiny neurons were analyzed both qualitatively and quantitatively in three dimensions with a semiautomated microscope-computer system. From digitized image of the neurons, various metric parameters were estimated to characterize the dendritic tree.

In cases of Sch, degenerative changes in the dendrites of OT spiny neurons were revealed. A decrease in the maximal radius of the dendritic tree and total length of dendrites were accompanied by an increase in the length density of dendrites. Hypertrophy and a more-intensive GFAP reaction of astrocytes were found in OT of Sch.

Based on these results, one can hypothesize that OT spiny neurons in Sch are involved in the process of dendritic reorganization, including degenerative changes in dendrites.