BACKGROUND: In patients with intracerebral hemorrhage (ICH), besides the space-occupying effect of hematoma, hematomal component also causes the pathological changes of perihematomal region, including the death of neurons and glial cells, vasogenic brain edema, the destruction of blood brain barrier and so on, which are the important factors to influence the prognosis of patients. Therefore, it is necessary to perform fur ther investigation and study on the pathological characteristics of injury and death of brain nerve cells. OBJECTIVE: To observe the pathological changes of apoptosis and Caspase-3 expression in perihe matomal brain regions in patients with hypertensive ICH (HICH) in different stages of onset, and analyze their relationship. DESIGN: Case-control observation. SETTING: Departments of Neurosurgery and Pathology of Beijing Chuiyangliu Hospital. PARTICIPANTS: Totally 19 patients with HICH, including 12 male, 7 female, aged (58.3±12.8) ranging from 49 to 78 years, whose mean volume of hemorrhage was (48.6±16.4) mL, were involved . All the cases conformed to the diagnostic criteria of intracerebral hemorrhage formulated in the 4th National Cerebrovascular Dis eases Conference and were confirmed by skull CT scanning. Informed consents of operation and specimens were obtained from the patients and relatives.METHODS; ①Patients with HICH who had undergone surgical evacuation of an intracerebral hematoma by traverse temporal lobe approach in the Department of Neurosurgery, Beijing Chuiyangliu Hospital from Jan uary 2004 to July 2005 were involved. Nineteen specimens of brain tissue from perihematomal region of HICH patients in different phases served as patient group. Five specimens were obtained from distant regions of patients in the super-early phase as the control group. According to the time from onset to operation, the 19 cases were divided into 3 groups: 6 cases in super-early phase(onset ＜ 8 hours), 8 cases in early phase (onset about 8 to 24 hours) and. 5 cases in delayed phase(onset ＞ 24 hours). The brain tissue obtained from distant regions of hematoma was preserved for control group (5 cases). ②All the specimens were subjected to terminal deoxynucleotidyl transferase-mediated deoxyuridine 5-triphosphate nick-end labeling (TUNEL) staining and Caspase-3 immunohistochemical staining. The change rule of positive cells was observed with image analyzer, and the relationship between apoptotic cells and Caspase-3 positive cells was analyzed. ③ Analysis of variance and t test were used for comprising the difference of measurement data, and liner correlation analysis was performed. MAIN OUTCOME MEASURES: ①Changes of cell apoptosis and Caspase-3 expression in brain tissue of perihematomal region of HICH patents in different phases. ② Correlation of cell apoptosis and Caspase-3 expression.RESULTS: Cell apoptosis: TUNEL positive cells were hardly or occasionally found in each visual field in the control group, while the number of apoptotic cells in 3 different phases in the patient group was all higher than that of control group, and considerable TUNEL positive cells were found in the super-early stage; The number of TUNEL positive cells reached peak at 8 to 24 hours in early phase, and then declined rnndelayed phase, but was still higher than that in the super-early phase(F=92.34, P ＜ 0.01 ). ②Caspase-3 protein expression: Caspase-3 positive cells were hardly seen in each visual field in the control group; Considerable Caspase-3 positive cells were found in the super-early group; The Caspase-3 positive cells were significantly increased and reached the peak in the early-phase, and then declined almost to the same level in delayed phase compared with the super-early phase (P ＞ 0.05). There was no significant difference in the number of Caspase-3 positive cells between super-early phase group and delayed phase group, but significant difference among the other groups (F =143.23, P ＜ 0.01). ③ Correlation analysis: There was significantly positive correlation between Caspase-3 and TUNEL positive cell counts (r=0.79, P ＜ 0.01 ).CONCLUSION: ① A lot of apoptotic cells existed in the brain tissue of perihematomal region. The number of apoptotic cells changes with the time of hemorrhage: it is in rise period and reached peak 24 hours before hemorrhage, but is declined 24 hours later. ② Caspase-3 is involved in the apoptosis after cerebral hemorrhage. It is one of signal transduction pathways of apoptosis, and is closely related to apoptotic degrees after cerebral hemorrhage.