Behavioral and Immunohistochemical Characterization of 6-Hydroxydopamine Induced Rat Models of Parkinson's Disease

ABSTRACT

There are several methods with which 6-hydroxy-dopamine is injected into the nigrostriatal pathway in rats for making models of Parkinson's disease. One is a complete lesion model in which A9 and A10 dopamine cells are destroyed, and the other one is a partial lesion model in which only A9 dopamine cells are destroyed. The aim of this study is to establish the model most suitable for transplantation of neural tissue. First, the behavioral change was investigated after dopamine releasing(amphetamine) or dopamine agonist(apomorphine) substances were injected. And then, immunohistochemical staining for tyrosine hydroxylase(TH) of the striatum and the substantia nigra was performed. Sixteen complete lesion models of Brundin, 4 complete lesion models of Perese, and 5 partial lesion models of Perese were made. The rotation response to amphetamine injection(5mg/kg, intraperitoneally) was checked 2 weeks after lesion making. For 6 rats, which showed rotation more than 7 turns/minute with amphetamine, the rotation response to subcutaneous injection of apomorphine was examined. Five complete lesion model of Brundin, 1 partial lesion model of Perese and 4 complete lesion model of Perese demonstrated rotation above 7 turns/minute in amphetamine test. Immunohistochemical staining of substantia nigra and corpus striatum for TH was faint on the lesioned side in rats which showed rotation above 7 turns/min in amphetaine-induced rotation test, irrespective of the kinds of model, while those ares of the normal side showed dense staining for TH. However, the results of immunohistochemical staining did not coincide with the results of rotation test by apomorphine.