To observe the evolution of astrocytes, GDNF, BDNF and Jak-STAT signal pathway after spinal cord ischemia-reperfusion injury in rabbits.

Spinal cord ischemia was induced by means of balloon occlusion of the infrarenal aorta for 22 minutes in 54 male New Zealand white rabbits. We assigned rabbits to 9 groups(n=6), one sham group, eight operation groups. The operation process in the sham group was the same as the operation group except the ischemia reperfusion of the spinal cord. At 0 h, 1 h, 2 h, 3 h, 8 h, 24 h, 48 h and 72 h after reperfusion, animals were sarcrificed and the spinal cord was removed for histologic, immunohistochemical study and western blotting.

Normal neurons were decreased with the extension of reperfusion time. Levels of GFAP increased at 3 h and reached a peak at 48 h after reperfusion. GDNF was increased reaching two peaks after injury, the first peak was at 3 h, the second was at 72 h. BDNF level was increased and peaked at 24 h after reperfusion. The expression of p-STAT3 showed a biphasic pattern which peaked at 1h and 48 h. GFAP, GDNF, BDNF were rare and the level of p-STAT3 could be neglected in sham group.

Spinal cord ischemia-reperfusion injury could induce the activation of astrocytes, the expression of GDNF, BDNF and the activation of Jak-STAT signal pathway. They showed different expression rules in this study.

Spinal cord; Injury, ischemia-reperfusion; Astrocytes; GDNF; BDNF; Jak-STAT signaling pathway