INITIAL CYCLOSPORINE-A BUT NOT GLUCOCORTICOID TREATMENT PROMOTES RECOVERY OF STRIATAL DOPAMINE CONCENTRATION IN 6-HYDROXYDOPAMINE LESIONED MICE

We examined the effects of cyclosporin A (CsA) and glucocorticoid (GC; hydrocortisone sodium succinate) in a mouse model of experimental par kisonism, GC or CsA was administered 30 or 60 min, respectively, prior to intracerebroventricular injection of 6-hydroxydopamine, followed b y injection of a similar dose of each drug 3 h later. CsA reduced the extent of depletion of striatal concentrations of dopamine (DA) and di hydroxyphenylacetic acid (DOPAC) associated with dopaminergic neuronal degeneration. GC reduced the extent of homovanillic acid (HVA) deplet ion in the same region. A combination treatment with CsA and GC did no t produce a further enhancement of the recovery of striatal concentrat ions of monoamines observed with CsA only. Our findings demonstrated t he beneficial effects of initial CsA treatment in experimental models of parkinsonism and further support the usefulness of CsA in the treat ment of Parkinson's disease. (C) 1997 Elsevier Science Ireland Ltd.