Immunofluorescence laser confocal expression and localization study of rat nerve growth guidance cues Netrin-1 and Slit2 after spinal cord injury

OBJECTIVE: To observe the expression and distribution of adult rat axon guidance cues Netrin-1 and Slit2 at different time points after spinal cord injury and to investigate the guidance mechanism of regenerated axons. METHODS: Twenty adult Sprague Dawley (SD) rats were divided randomly into five groups with 4 in each. Four groups of them were used to make Allen's spinal cord punch models and we took materials randomly from one of them on the 2nd, 4th, 7th and 14th day respectively after operation. The left one group was taken as the control group. Immunofluorescence laser confocal scan was used to examine the co-expression and localization of Netrin-1 and Slit2 proteins in the injured site of the spinal cord. RESULTS: Within two weeks after SCI, the expression of Netrin-1 and Slit2 proteins increased temporarily and there was co-expression of them on the neuron plasma membrane.CONCLUSIONS: Synchronous high expression and co-expression of axon attractant Netrin-1 and repellent Slit2 are found in the adult rat injured spinal cord in the damaged local and vicinity parts, and probably, they act as the key regulators of axon guidance regeneration.