Efecto neuroprotector de la administración sistémica de (-) nicotina en ratas hemiparkinsonizadas

Neuroprotective effect of the (-) nicotine systemic administration in hemiparkinsonian rats. It is very important the manipulation of the cholinergic system in the experimental Parkinsonism through systemic (-) nicotine administration since the finding about the less incidence of Parkinson’s disease between smoking people. The following experimental groups were evaluated: 1. non-treated rats (n = 11), 2. rats with lesion of the substantia nigra compacta (SNc) (n = 10), 3. rats treated with (-) nicotine and SNc lesioned (n = 18), 4. sham operated rats (n = 10), 5. rats with false pharmacological treatment and SNc lesioned (n = 10). The motor execution, motor asymmetry, extracellular concentration of glutamate (Glu), γ-aminobutiric acid (GABA) in pedunculopontine nucleus (PPN), the survival of dopaminergic cells and the striatal expression of neurotrophic factors were the variables studied. The rats treated with (-) nicotine showed an improvement in the motor execution and a minor number of errors during the execution in the Cross Bridges Test in comparison with the hemiparkinsonian rats without pharmacological treatment. In addition, the pharmacological treatment induced a decrease in the extracellular levels of Glu and GABA in PPN and also it attenuated the motor asymmetry of the rats. Simultaneously, the (-) nicotine administration promoted a higher brain derived neurotrophic factor striatal expression joint to a survival of the dopaminergic cells in the SNc. Ours results suggests a neuroprotector role for the (-) nicotine schedule applied in the present study.