Age, strain, and semi-chronic hydergine treatment effects on motor activity and neuronal nucleic acid-protein metabolism in male mice

This study was designed to examine the effects of Hydergine (DHET), co-derg ocrine mesylate, treatment on motor activity and neuronal nucleoprotein met abolism in several motor areas of the aging rodent brain, specifically the caudate-putamen (CP), the substantia nigra (SN), and the cerebral cortex la yer V (CX). Three age soups of two different strains of mice were used whic h represented two different aging rates: DBA/2 male mice (short lived) and C57BL/6 male mice (long lived). A representative sample of each age soup wa s injected (IP) daily with a single dose of either DHET (1 mg/kg) or vehicl e (0.9% saline) solution for one month. Total spontaneous motor activity wa s measured using a File apparatus to assess the functional ability of the s elected brain areas. Histochemical parameters measured included the relativ e RNA and protein contents from a homogeneous population of neurons within each nuclei. The RNA and protein contents were assessed with a scanning mic rodensitometer using azure B and Coomassie staining protocols, respectively . The results of this study provide evidence that DHET does have significan t effects on neuronal functioning in the motor compartments studied at the behavioral as well as the histochemical level for DBA/2 male mice. The C57B L/6 strain showed parallel, but less significant, changes in the histochemi cal parameters and no statistical differences in motor activity. In additio n, DHET treatment produced no sign of neurotoxicity within any of the brain nuclei in either strain. (C) 2000 Elsevier Science Inc. All rights reserve d.