BEHAVIOURAL ANALYSIS OF UNILATERAL MONOAMINE DEPLETION IN THE MARMOSET

• DOI: 10.1093/brain/115.3.825
• Publication Date: 2007-01-04T04:52:09Z
• Authors: L. E. ANNETT; D. C. ROGERS; T. D. HERNANDEZ; S. B. DUNNETT
• Keywords: Putamen; Caudate nucleus; Medial forebrain bundle

Unilateral stereotaxic injections of 6-hydroxydopamine (6-OHDA) into the nigrostriatal bundle marmosets (Callithrix jacchus) produced substantial losses tyrosine hydroxylase immunoreactive neurons from substantia nigra, and mean dopamine (DA) depletions 98–99% in caudate nucleus, putamen nucleus accumbens, 91-97% frontal cortex, on side lesion. Noradrenaline (NA) 5-hydroxytryptamine (5-HT) levels were also affected. Behavioural tests conducted pre-operatively at regular intervals during 6mths following surgery revealed persistent deficits lesioned as a group compared with sham-lesioned controls, although individual sometimes recovered or showed no initial deficit some tests. The main behavioural effects lesions follows: (i) an increase time spent head positioned ipsilaterally respect to rest body; (ii) ipsilateral spontaneous amphetamine-induced rotation, occasional intermittent periods contralateral rotation biases recorded; (iii) apomorphine-induced rotation; (iv) reduced activity; (v) hand preference conveyor belt task, skill (measured percentage errors when speed was increased) not affected; (vi) neglect stimuli, both where monkeys often failed respond trails which apple pieces arrived side, test sensorimotor adhesive labels placed around feet. Comparisons biochemical measures lesion scores suggest that DA excess 95% are essential for long-term deficits.