Effect of CNTF on Ca~(2+) level in spinal cord motor neurons after sciatic nerve anastomosis at different time points post-injury

AIM:To research on motor neurons protection of spinal cord segment corresponding to traumatic sciatic nerve injury by ciliary neurotrophic factor(CNTF).METHODS:The sciatic nerves of both sides at rats were transected and repaired after a delay of immediately,3,7,14,21 d and CNTF treatment was given.They were sacrificed after 3 d and detected spinal Ca2+ concentration.Sacrificed them after 28 d and counted apoptotic cells with staining,HE detected morphology changes of L4-6 spinal neurons,morphology observation of nerve fibers on nerve anastomosis.RESULTS:The number of TUNEL positive cells in five groups of medication group was less than that in non-medication group and saline group.The number of apoptotic cells in 7 d group was smaller than that in non-medication group and saline group and was the smallest compared with the other four groups(P0.05).While increase amplitude of Ca2+ ionic concentration and plasma endothelin level was lower.some nerve fibers passed the cut in medication group on 28th day.More fibers were found in 7,14 d group,but irregularly.Fewer fibers were found in non-medication group and saline group.CONCLUSION:That sciatic nerve is transected and repaired at different time can cause apoptosis of spinal cord anterior horn motor neurons.After the sciatic nerves at rats were transected and repaired,early use of CNTF can decrease Ca2+ in acute spinal tissues and keep ion balance in and out of cells.This may decrease apoptosis of spinal motor neurons and keep regeneration of peripheral nerve axon.