An NR2B-Dependent Decrease in the Expression of trkB Receptors Precedes the Disappearance of Dopaminergic Cells in Substantia Nigra in a Rat Model of Presymptomatic Parkinson's Disease
Figure 3
Unilateral 6-OHDA intrastriatal injection results in a significant decrease in the number of trkB-IR cells in ipsilateral SNc at 7 and 14 days after the injection. (a) Percentage of trkB-IR cells in rat ipsilateral SNc compared to the contralateral side after unilateral 6-OHDA (black columns) or ascorbic acid (sham, white columns) intrastriatal injections. Number of cells with trkB-IR signals in contralateral SNc of ascorbate-injected rats per area unit per slice was , , and cells/mm2, at 4, 7, and 14 days after injections, respectively. In the case of 6-OHDA-treated rats, number of cells with trkB-IR signals in contralateral SNc was , and cells/mm2, at 4, 7, and 14 days after 6-OHDA injections, respectively. (b) Percentage of trkB-IR cells in the ipsilateral SNR compared to the contralateral side, at 7 and 14 days after unilateral intrastriatal injections of 6-OHDA (black columns) or ascorbic acid (sham, white columns). Number of cells with trkB-IR signals in contralateral SNR of ascorbate-treated rats was and cells/mm2, at 7 and 14 days after injections, respectively. In the case of 6-OHDA-treated rats, the number of cells with trkB-IR signals in contralateral SNR amounted to and cells/mm2, at 7 and 14 days after toxin injections, respectively. rats under each experimental condition. The different experimental groups were compared by a Kruskal-Wallis nonparametric ANOVA, followed by a -test. * compared with sham-treated rats.
