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Aged monkeys used to study changes in human ageing and Parkinson’s Aged monkeys may be a useful model for mimicking changes seen in human ageing and early Parkinson's disease (PD). Recent research by Embourg and colleagues has shown that age-related motor function loss in monkeys is associated with spontaneous decreases in nigral brain cells. Compared with young monkeys, aged rhesus monkeys showed significant motor loss when they were assessed on a fine motor task, cage activity and clinical motor function. Measurements of the substantia nigra area of the brain revealed a significant age-related loss of tyrosine hydroxylase and dopamine transporter-immunoreactive nigral brain cells. Although the role of dopamine dysfunction is well established in PD, the effect of nigrostriatal degeneration on motor performance during normal aging is less well understood. The correlation of motor function loss with the loss of tyrosine hydroxylase and dopamine transporter-immunoreactive nigral brain cells suggests that aged monkeys may provide a useful model for studying the changes seen in human ageing and early PD. Source: Emborg ME et al. Journal of Comparative Neurology 1998; 401(2): 253-265. Updated 1st December 1998 Glial cell line-derived neurotrophic factor is neuroprotective Glial cell line-derived neurotrophic factor (GDNF) shows powerful neuroprotective and neurorestorative properties in preclinical studies. In parkinsonian monkeys, GDNF treatment improved bradykinesia, rigidity and postural instability. Grondin and colleagues report that adult midbrain dopamine neurons stimulated by GDNF show increased cell size, axonal lengthening, and expression of phenotypic markers. The neurorestorative effects of a single dose of GDNF last for at least one month and can be maintained by monthly injections (in monkeys). GDNF also induces neuroprotective changes in dopamine neurons, which are evident within hours following administration of GDNF in rodents. GNDF is distantly related to the transforming growth factor superfamily and is widely expressed in many neuronal and non-neuronal tissues. It promotes recovery of the injured nigrostriatal dopamine system and improves motor functions in rodent and monkeys models of Parkinson's disease. Source: Grondin R et al. Journal of Neurology 1998; 245(3): 35-42. Updated 1st December 1998 -- Cheers , +----| Joao Paulo de Carvalho |------ + | [log in to unmask] | +--------| Salvador-Bahia-Brazil |------+