Chronic supranigral infusion of BDNF in normal and MPTP-treated common marmosets

BDNF or vehicle were administered by unilateral supranigral infusion in nor mal and chronically lesioned MPTP-treated common marmosets (Callithrix jacc hus) for four weeks and locomotor activity, disability and response to apom orphine were assessed with nigral TH, GFAP and GAD immunoreactivity and str iatal [H-3]mazindol autoradiography. Selective contraversive orientation an d ipsilateral neglect evolved in MPTP-treated marmosets receiving BDNF with no significant difference in disability or locomotor activity when compare d to the vehicle-infused group. Apomorphine produced an ipsiversive rotatio nal bias in BDNF-treated animals. In normal animals infused with BDNF contr alateral neglect, ipsiversive turning, postural instability and ataxia rapi dly evolved. In MPTP-treated marmosets BDNF caused increased ipsilateral st riatal [H-3]mazindol binding with increased somatic size and staining inten sity in GAD-immunoreactive cells and a 10-20% loss of nigral TH-immunoreact ive cells with increased GFAP staining. In normal common marmosets, both ve hicle and BDNF infusion decreased nigral TH-immunoreactivity. Chronic supra nigral infusion of BDNF alters motor behaviour and spatial attention in MPT P-treated marmosets which may reflect altered function in residual nigral d opaminergic neurons and brainstem GABAergic neurons and in normal animals p roduces behavioural and histological signs of nigrostriatal hypofunction.