Suppression of activation of c-fos protein in the striatum by systemic administration of nitroglycerin in a rat model of Parkinson’s disease

Abstract

We found sustained activation of the proto-oncogene c-los in neurons of the medial and dorsal neostriatum and suppression of this activation in NO-synthase (NOS)-containing cells within the islands of Calleja after unilateral lesions of the dopaminergic mestmtriatal system induced by 6-hydroxydopamine (6-OHDA). Systemic administration of nitroglycerin (NTG) resulted in a decreased expression of c-Fos protein in the dorsal part of the denervated neostriatum: respective numbers of Fos-positive neuronal nuclei were 420.71 _+_ 21.32 in control and 141.38 _+ 11.48 after NTG injection (the mean numbers in 50-/~m-thlck slices). However, other brain structures, NTG evoked sustained expression of c-Fos protein in the groups of NOS-containing neurons and sources of catecholaminergic projections involved in the control of cardiovascular reactions. We hypothesize that systemic administration of an NO donor and a potent vasodilator, NTG, partially normalized an excessively increased glutamate level in the denervated neostriarum manifested in c-Fos protein expression.