Abstract:

Objective To observe the long-term behavioral changes in movement, emotion, and learning and memory of newborn mice with hypoxic ischemic brain damage (HIBD). Methods A total of 50 ten-day old newborn C57BL/6 mice were divided into control group (n = 20) and HIBD group (n = 30). The left common carotid artery was ligated in HIBD group and stayed in anoxic chamber for 45 minutes. All the mice were tested with suspension test, light/dark box test, elevated plus maze test, object recognition test and Y maze test two months after surgery. Results There were 19 mice modeled successfully. Compared with the control group, the suspension test scores decreased (t = 2.785, P < 0.05); the time of latency of light/dark box test increased (t = -4.320, P < 0.001), the time and frequency in light box decreased (t > 2.603, P < 0.05); the time in open arm decreased (t = 4.576, P < 0.001) and the time in close arm increased (t = -3.287, P < 0.01) for the elevated plus maze test; the time nearing old object increased (t = -2.116, P < 0.05) and object recognition index decreased (t = 2.823, P < 0.05) for object recognition test; the time in the initial and novel arms decreased (t > 2.191, P < 0.05) for Y maze test in HIBD group. Conclusion The long-term disorders of behavior may include disabilities of motor, learning and memory, and disorder of anxiety, in newborn mice with HIBD.

Key words: hypoxic ischemic brain damage, motor, recognition, anxiety, mice