Enhanced Neuroprotection Of The Striatal Dopaminergic Neurons By Baicalein In 6-Ohda-Treated Aged Rat
Background & objectives: In young adult rats, baicalein can protects against 6-hydroxydopamine-induced loss of
striatal dopaminergic neurons when administered prior to the 6-hydroxydopamine. The present study was undertaken to
determine if baicalein would provide similar protective effects in aged rats. Literature is silent about it. Methods: Sprague-
Dawley rats of 22-24 months of age were given an intraperitoneal injection of baicalein or baicalein vehicle i.e.5% Dimethyl
Sulfoxide for 7 days followed 2 h later with an intrastriatal injection of 6-hydroxydopamine. Various behaviour and
immunohisotochemical tests were performed to investigate the beneficial effects of baicalein. Results: Statistically significant
difference was found between post-lesion values of all groups (ANOVA, P<0.001 in apomorphine-induced rotational
behaviour, staircase test (success rate) and disengage time; P<0.05 in stepping test, initiation time and postural balance test.
Baicalein promotes significant cell survival in the striatum of all age groups; however, the percent survival was lowest in the
22-24-month-old animals. Interpretation & conclusion: Overall, these results indicate that baicalein can protects striatal
dopaminergic neurons against the effects of 6-hydroxydopamine in aged as well as adult rats. However, the extent of
protection is less in the aged animals.
Index Terms— Aged rat, Baicalein and 6-hydroxydopamine.