A Study on Central Neural Pathways of the Sciatic and Femoral Nerves of the Rat

Kim, Eun Sang; Lee, Bong Hee; Kim, Myeong Ju; Chang, Ka Young

Abstract

The central neural pathways of the sciatic and femoral nerves of the rat were identified with tracing methods of fluorogold, cholera toxin-horseradish peroxidase and Bartha strain of pseudorabies virus as neurotracers. After injections of fluorogold and CT-HRP into the femoral and the sciatic nerves respectively, the spinal cords were removed and processed for fluroscent microscopy and histochemistry. Lower motor neurons were multipolar in shape and located in the ipsilateral L3-L5 and L5-S1 segments. The location of the femoral LMN's were ventromedial to those of the sciatic nerve. There was no double labeled neurons and the lower motor neurons of the femoral nerves were located in ventromedially to sciatic LMN in the spinal cord. After injections of fluorogold and PRV-Ba into the femoral and the sciatic nerves respectively, the fluorogold labeled neurons were identified only in the ventral horn of ipsilateral L3-L5 segments and PRV-Ba labeled cells in L5-S1 segments. Besides L5-S1 segments, some PRV-Ba labeled cells were found in the ipsilateral L3-L4 segments and a portion of them were double labeled with fluorogold and PRV-Ba. Sequential tracing of retrograde labeled cells was done after injection of PRV-Ba into the femoral and sciatic nerves. The upper motor neurons of both nerves were mostly ovoid or polygonal in shape and present in the same nuclei of supraspinal central nervous system. In conclusion, lower motor neurons of the femoral and the sciatic nerves were arranged in somatotopic organization and some of them were connected with synaptic route. But the central pathways of both nerves were similar in locations.