Figure 5.

Melatonin neuroprotective effect on dendritic arbors damaged by okadaic acid in the hilar hippocampus. Rat hippocampal slices (400 µm) were cultured for one week and treated for 6 or 8 h. Slices were fixed as described in methods and 50 µm cryosections were processed for MAP2 detection by immunohistochemistry. Representative images of MAP-immunostained treated slices are shown as follows: (a) vehicle (VEH); (b) 45 nM okadaic acid (OKA); (c) 100 nM melatonin (MEL); (d) MEL before OKA; (e) simultaneous MEL and OKA; (f) OKA before MEL. Inserts highlight the dendritic arbors of hilar neurons. Scale bar in (f): 100 µm.