FIG. 5.

Neuronal morphology and microarchitecture in the hippocampus of sham-operated (A–D) and head-injured (E–H) wild-type and Rag1^−/− mice, as determined by immunohistochemistry in 10-μm-thick coronal brain cryosections. A monoclonal anti-NeuN antibody was used as a neuron-specific marker. Adult male C57BL/6 and Rag1^−/− mice (n=3 per group) were euthanized at 24 h after the surgical procedure. The lower panels represent fivefold magnifications of the boxed areas in their respective upper panels (100×and 20×original magnifications), depicting the hippocampal CA3/CA4 cell layers. Sham-operated wild-type (A and B) and Rag1^−/− mice (C and D) showed a similar hippocampal structure and neuronal morphology. In contrast, head injury induced cellular disruption and changes in neuronal morphology in the CA3/CA4 cell layers; however, this did not differ in extent between wild-type (E and F) and Rag1^−/− mice (G and H).