Effect Of IGF-1 On Cytochrome-C And Caspase-3 Expression Of Hypothalamus In The Acute Phase And Anxiety Behavior In The Recovery Period Of Neonatal Mouse With Hypoxic-ischemic Brain Damage

Objective: To research the effect of IGF-1 on Cytochrome-C and Caspase-3 expression of hypothalamus in the acute phase and anxiety behavior in the recovery period of Neonatal Mouse with with hypoxic-ischemic brain damage(HIBD).Methods: Using the modified Rice method to make the HIBD animal model. The right common carotid artery of 7-day-old C57/BL neonatal mouse were permanently ligation and placed in the anoxic compartment(including 8% oxygen and 92% nitrogen) for 2 hours.The 7-day-old C57/BL neonatal mouse were fall into control group(n=42), HIBD group(n=42) and HIBD+IGF-1 group(n=42) randomly.The control group just separated the dexter common carotid artery without ligation and hypoxia treatment. After the operation, HIBD+IGF-1 group injected IGF-1 immediately, HIBD and control group injected saline solution at the same time with same amount.36 mice were selected randomly in each group.Took there brain tissues for immunofluorescence staining technique on postoperative 0h, 3h, 6h, 12 h, 24 h, 48 h time point(n = 6) to detect cytochrome-c and Caspase-3 expression of hypothalamus.Elevated plus maze test and open field test were used to assess the anxiety behavior at the age of 21, 28, 42 days.Results: 1.The Cyt-C and Caspase-3 OD value were increased in HIBD group at the time of 3h, but compared with control group there was no obviously differents(P > 0.05). At the time of 6h, 12 h, 24 h, 48 h the Cyt-C and Caspase-3 OD value in HIBD group were higher than that of HIBD+IGF-1 group and control group(P < 0.05),and HIBD+IGF-1 group were higher than control group(P < 0.05).At the each time point,24 h time points had the highest Cyt-C and Caspase-3 OD value. 2.At P21, P28 and P42 the ratio of open arm entry,the ratio of open arm residence time in HIBD group was higher than control group. The ratio of open arm entry and the ratio of open arm residence time has no significant difference between the control group and HIBD+IGF-1 group.The total times entry in each group has no significant difference at P21, P28 and P42. 3.At P21, P28 and P42 the percentage of movement distance in area centralis,the motion time in area centralis in HIBD group was higher than control group. The percentage of movement distance in area centralis and the motion time in area centralis has no significant difference between control group and HIBD+IGF-1 group.The total movement distance in each group has no significant difference at P21, P28 and P42.Conclusion: 1.IGF-1 can reduce the Cyt-C and Caspase-3 expression of hypothalamus of neonatal mice with hypoxic ischemic brain damage; 2.The adolescent anxiety behavior of C57/BL mice with hypoxic ischemic brain damage will reduce, and the exogenous IGF-1 can make the anxiety behavior back to normal levels.