Abstract
Studies on the molecular basis of neurological and psychiatric disorders often rely on the precise determination of specific proteins in brain tissues. In this study, we have developed a method for measuring the levels of the neural-specific growth-associated protein, GAP-43, in human postmortem brain specimens. This rapid and quantitative method is based on immunodetection procedures. Briefly, synaptosomal plasma membranes (SPMs) are deposited onto polyvinylidene difluoride (PVDF) membranes via a dot-blotting apparatus, followed by specific GAP-43 detection using a monospecific polyclonal antibody. Overall, the dot-blot procedure provided several advantages over Western blots and one-dimensional and two-dimensional polyacrylamide gels. The assays were more sensitive, reproducible, and allowed the rapid and simultaneous determination of multiple samples. Using this technique, we examined the levels of the GAP-43 protein in Brodmann’s areas 17, 20, and 10 of schizophrenic and age-, sex- and postmortem interval (PMI) matched controls. These studies revealed an increase in the levels of GAP-43 in visual association and frontal cortices (areas 20 and 10) of schizophrenic brains. Given the relationship of GAP-43 expression with the establishment and remodeling of neural connections, our results support the hypothesis that schizophrenia is associated with a perturbed organization of synaptic connections in associative areas of the human brain.
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Abbreviations
- GAP-43:
-
43-kDa growth-associated protein
- PMI:
-
postmortem interval
- SPM:
-
synaptosomal plasma membrane
- PVDF:
-
polyvinylidene difluoride
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Sower, A.C., Bird, E.D. & Perrone-Bizzozero, N.I. Increased levels of GAP-43 protein in schizophrenic brain tissues demonstrated by a novel immunodetection method. Molecular and Chemical Neuropathology 24, 1–11 (1995). https://doi.org/10.1007/BF03160108
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DOI: https://doi.org/10.1007/BF03160108