The effects of protein kinase C activator phorbol dibutyrate on traumatic brain edema and aquaporin-4 expression.

BACKGROUND: Aquaporin-4 (AQP4) is the major water channel in the central nervous system. Brain edema emerges from increased AQP4 expression in traumatic brain injury (TBI). Cell line studies have shown that the protein kinase activator phorbol ester exerts a suppressive effect on AQP4 and water permeability. The aim of this study was to investigate the effects of a phorbol ester, phorbol dibutyrate (PDBu), on increased TBI AQP4 expression and accompanying brain edema. METHODS: Fifty-six male Wistar rats were first divided into two groups: the edema group, in which the percentage of water in brain tissue would be evaluated, and the immunohistochemical group, allowing AQP4 expression to be determined. Both groups were further sub-divided into four groups consisting of 7 subjects. These four groups were as follows: sham-operated control group, severe diffuse TBI group, 0.9% saline-treated diffuse TBI group, and the PDBu-treated diffuse TBI group (2300 µg/kg, iv). The results were evaluated statistically. RESULTS: PDBu treatment significantly reduced brain water concentration (p<0.001). Furthermore, PDBu was found to reduce trauma-induced AQP4 upregulation (p<0.05). CONCLUSION: This study showed that traumatic brain edema was prevented by intravenous PDBu administration via AQP4 downregulation, supporting the idea emphasizing the importance of AQP4 expression control in TBI.

Analyses of clinical prognostic factors in operated traumatic acute subdural hematomas.

BACKGROUND: Traumatic acute subdural hematoma is the most lethal of all head injuries. METHODS: In this study, 113 patients with the diagnosis of posttraumatic acute subdural hematoma, who were operated between 1998 and 2006, were reviewed retrospectively. Statistical analysis was performed to detect any effects of the variables of age, Glasgow Coma Scale (GCS) score on admission, time interval between the trauma and operation, and abnormality in the pupil reaction on the disease mortality and morbidity. RESULTS: Results obtained in the study are discussed and compared with the related current literature. The overall mortality in 113 patients was 56.6%. CONCLUSION: According to the results, the most important determinants of the prognosis are GCS score of the patient on admission, abnormality in pupil reaction, timing of the operation, and the patient's age.