The Neuroprotective Effect Of G-CSF In Acute Brain Ischemia

Objective In order to understanding the neuroprotective effect of granulocyte colony-stimulating factor (G-CSF ) in acute brain ischemia.The neurological function, MR image and pathological methods were used to modified the effect of G-CSF in transient MCAO animal model in rat. Material and method (1) The middle cerebral artery occlusionmodel in rat: The method which was first described by koixumi and zea longa, was used to make transient MCAO animal model, the occlusion was lasted for 1hour then reperfused by through out the nylon filarment. (2) The measurement of cerebral blood flow during the operation of transient MCAO in rat: in order to make sure the damage area in the different groups were at the same level, the CBF was checked by laser Doppler during the whole occlusion time. (3) MR image study: After the anesthesia,the rat was put on the carriage ,then the T2 and DWI was measured and during the whole process the respiratory frequency and PO2 was checked. (4) The brain section: After the perfusion from heart, the brain of rat was moved and cut as MR image level. (5) The NSS scale: the NSS Determination was taken from 4 hour after the operation, to 8days after the operation. (6) The measurement of damage area: the section that at the level of optic chiasma was selected to measured the damage area and edema by image analyzer. (7) Immunohistochemistry staining: The SP and SABC methods was used to stained the simples the antibody was anti-ED-1, anti-GFAP, anti-NeuroN, anti-MAP-2, the TUNEL was also used to check the apoptosis cell. (8) The account of positive cell: 6 simples was selected to account the positive cells in every group, in each section 5 area was to account the number of positive cells, the average of the 5 area was the final result of one simple. (9) The injection of G-CSF: The G-CSF was Subcutaneous injected every day. Results During the operation the CBF was reduced more than 20%, and there were no significant difference in the all groups by statistic analysis. The NSS scale result: In preinjection part: compared with control group and treatment group, It was no difference at first 3 times results (4 hour, the 1st day and 2 day after operation). But from 3 day after operation to 8 day after operation there was significant difference in two groups. In delayed injection part: compared with control group and treatment group, It was no difference at first 4 times results( 4 hour, 1 day, 2 day and 3 day after operation). But from 4 days after operation to 8 days after operation there was significant difference in two groups.It was shown that both in the two partthe G-CSF has the neuroprotective effect. MR image study result: In the preinjection part, the lesion of two groups at the 1 day after operation was no difference. At the 8 day after operation there was significant difference in the 2 groups, for the control group the lesion was similar as 1 day after operation; but for the treatment group the lesion was decreased significantly compared with 1 day after operation. At the 22 day after the operation the lesion of two groups was significant difference. In the treatment group some cases was shown negative although the image of at 1 day and 8 day was positive, but in the control group there was no similar case. In the delayed injection part, It was shown the same result as preinjection part. At the 1 day after operation there was no difference in two groups, at 8 day after operation the lesion was reduced by G-CSF, and It was significant difference between two groups. The result was shown that the damage area was reduced significant by G-CSF. The measurement of damage area and pathological study result: In the preinjection part, the damage area level was significant difference between two groups. Brain atrophy level was also shown the same result. In the control group the border of damage area was sharp, in the area there were lots of macrophage,the structure of brain was extinction,the core of damage area was colliquation; In the treatment group, the structure was very well in the damage area and the colliquation was no observed, the cellular proliferation of glial cell was existed in the damage area. The lesion of some treated cases was only shown in pathological study. In the delayed injection part: the damage area level was significant difference between two groups. But the brain edema level was same. The pathological changes was similar in the two groups, the level was lightly in the treatment group.