Variation and significance of GDNFmRNA gene expression on sciatic nerve after spinal cord injury in rats

Objective To investigate the variation and significance of the gene expression of GDNFmRNA on sciatic nerve after spinal cord injury(SCI) in rats.Methods The specimen of sciatic nerve was taken after T 13 segments of spinal cord were injured by modified Allen crush method(10g×7 5cm).The level of GDNFmRNA was observed and compared before and after SCI,using semi quantitative RT PCR method with β Actin as a inner consult.Results Much minim expression of GDNFmRNA was found in sciatic nerve of normal adult rats,but it increased 4 times after 24 hours of SCI,15 times in 72 hours,3 times in 7 days and slight higher than normal level in 10 days.Conclusion It should be one kind of self protective reactive models for sciatic nerve to express high standard GDNFmRNA through neuron-axon-target route in the early stage after SCI.GDNF should be supplied early when it was applied to treat SCI.