Fig. 6

Morphological evidence of the protective effect of PLA against LPS-induced damage to dopaminergic neurons in the SN. Rats were randomly grouped and then treated with PLA (25, 50 and 75 mg/kg) or vehicle for 6 weeks after LPS injection. On day 42, rats were deeply anesthetized and transcardially perfused with 4 % paraformaldehyde and processed as above. Frozen sections at a thickness of 40 μm were cut and TH was detected by immunohistochemical staining to show dopaminergic neurons in the SNpc. (A1–A4) sham-operated group, TH staining was similar on the non-injected (A2) and injected (A3) side; (B1–B4) model group, LPS-injected followed by vehicle treatment, an obvious loss of TH-ir cells was seen on the injected side (B3); (C1–C4, D1–D4, and E1–E4) the LPS-injected group followed by treatment with 25, 50 and 75 mg/kg PLA respectively, much more TH-ir neurons survived on the LPS-injected side compared to model group