RESUMEN
OBJECTIVE@#To observe the expression pattern of caspase-3 and HCLS1-associated protein X-1 (HAX-1) at different time after cerebral contusion in rat, and explore the new method for estimating the injury interval.@*METHODS@#The cerebral contusion model was established using adult SD male rats. Then the rats were randomly allocated into 8 groups: 2 h, 6 h, 12 h, 1 d, 3 d, and 7 d after cerebral contusion, sham-operation and normal control. Expression of caspase-3 and HAX-1 protein after cerebral contusion in rat was detected by Western blotting. Laser scanning confocal microscope was used to observe the number of HAX-1 positive cells and TUNEL-stained cells after cerebral contusion.@*RESULTS@#The expression of caspase-3 increased parallelly with the time after cerebral contusion and reached the peak value on 3 d. The expression of caspase-3 decreased gradually and still maintained a high level expression on 7 d (P < 0.05). The expression of HAX-1 positive cell went up after injury, and reached the peak value at 6 h (P < 0.05), then turned down gradually after 12 h and went out of detection after 3 d. The number of TUNEL-stained cells increased obviously at 2 h and reached the peak value on 3 d. The number of TUNEL-stained apoptotic cells decreased gradually and still maintained a high level expression on 7 d (P < 0.05).@*CONCLUSION@#The expression of caspase-3 and HAX-1 after cerebral contusion has time sequential regularity, which may provide new evidence for forensic diagnosis of cerebral contusion interval.