Figure 11.
Histological findings after injections of isotonic (120 mm) MnCl2 in monkeys T and S. Panels on the left show thionin staining. Panels on the right show cytochrome oxidase activity. A, Monkey T. Thionin staining revealed no areas of cell loss or damage after the orbitofrontal MnCl2 injection. The needle track could be visualized, but the cortical tissue at the injection site could not be distinguished from the surrounding tissue. Cytochrome oxidase activity levels at the injection site also appeared unaffected. los, Lateral orbital sulcus; mos, medial orbital sulcus. B, Monkey S. Thionin staining revealed no areas of cell loss after the orbitofrontal MnCl2 injections. The needle itself did cause some tissue damage within OFC. Cytochrome oxidase activity levels appeared decreased in small regions near the injection sites. The tear from the needle itself can also be seen in this cytochrome oxidase section. C, Monkey S. Thionin staining revealed a small area of cell loss after the anterior cingulate MnCl2 injection. Cytochrome oxidase activity levels also appeared decreased in a small region near the injection site. cgs, Cingulate sulcus. Scale bars, 1 mm.