S-100B protein serum levels after controlled cortical impact injury in the rat

S-100B is described to provide information about the severity of brain damage in man. Estimation of serum markers appears to be an easy method of obtaining information regarding severity and outcome after head injury. However less is known about the post traumatic time course of this protein in the serum. The aim of this study was to provide further information about the posttraumatic enzymekinetik. 65 male Wistar rats were subjected to severe cortical impact injury (100 PSI, 2 mm deformation). Blood samples were drawn directly after trauma, then after 1 h, 6 h, 12 h, 24 h, and 48 h. In sham operated animals blood samples were drawn directly after craniotomy, then after 6 h and after 48 h. Also compared were S-100B serum levels at different severities in 20 rats (45 PSI, 75 PSI; 2 mm deformity) after controlled cortical impact to sham operated animals. S-100B serum levels were estimated with a commercially available enzyme immuno-assay (DAKO). The mean serum level in the sham group was 0.38 microg/l. Serum levels at 100 PSI differed statistically significantly directly after trauma up to 24 h. The 48 h S-100B levels showed no significant difference in the sham group. Serum levels at different severities differed significantly from the sham group, but did not differ concerning level of severity. The controlled cortical impact model is able to produce a raised serum level of the S-100B protein for 24 hours. Different trauma severities were not reflected.