Differential effects of unilateral striatal and nigrostriatal lesions on grip strength, skilled paw reaching and drug-induced rotation in the rat

Lateralised motor deficits associated with basal ganglia dysfunction were c ompared in separate groups of rats receiving unilateral 6-hydroxydopamine-i nduced lesions of the dopaminergic nigrostriatal pathway, quinolinic acid-i nduced lesions of the striatum, or sham control injections. Amphetamine ind uced ipsilateral rotation in both lesion groups, whereas a low ('supersensi tive') dose of apomorphine induced rotation only in the nigrostriatal lesio n group. Both lesions induced impairments in skilled paw reaching with the contralateral paw in the 'staircase' test; by contrast the striatal lesions also induced a marked impairment with the ipsilateral paw, which was unaff ected by the nigrostriatal lesion. A previously reported increase in grip s trength with the contralateral paw after nigrostriatal lesion was replicate d, whereas striatal lesions induced only minor bilateral deficits in this t est. The results are discussed in the context of the utility, reliability a nd validity of alternative tests of motor deficit in animal models of Parki nson's and Huntington's diseases. (C) 2001 Elsevier Science Inc.