Figure 2
The time courses of extracellular O 2 • ─concentration changes following impact injury to the rat spinal cord in saline-treated, MPSS-treated, and MnTBAP-treated groups. The procedure was described in detail in the Methods. O2• ─ was captured by perfusing cytochrome c through the microcannula. After three samples were collected at 20-min intervals to establish the basal level, a weight was dropped at time 0 onto the cord (25 g·cm) and sampling was continued for another 5 h at 20-min intervals. MnTBAP and MPSS were administered similarly, as in Figure 1. The perfusates were collected, centrifuged, and the absorbance of reduced cytochrome c was measured spectrophotometrically. MnTBAP, but not MP, significantly reduced O2• ─ levels.