Expression of c-fos and no-synthase activity in motoneurons and interneurons of the rat's spinal cord

Abstract

Introduction: The problem of the implementation of the accuracy and efficiency of motor skills is important in the producing of professional movements of any person, in sports, music, medicine, and particularly in post-stroke rehabilitation. Muscle proprioceptive impulses play an important role in the functioning of spinal motor centers. Excitable and inhibitory interneurons in dorsal and ventral horns of the spinal cord are important components of structures, which monitor physical activity. We have studied the expression of c-fos and NADPH-diaphorase-reactive neurons in the cervical spinal segments of rats. Materials and Methods: Six male Wistar rats were examined. Operant motor activity was realized in the course of 12 everyday 30-min-long training sessions. After 2 hours of the last training, all experimental rats were intracardially perfused through the ascending aorta. Fosimmunoreactive neurons were visualized immunohistochemically in the C6/C7 spinal segments in rats trained for operant movements. Fos-immunoreactive nuclei were revealed with standard avidinbiotin-peroxidase method, which used polyclonal rabbits’ antibodies directly against nuclear c - Fos protein. Histochemical labeling of neurons based on the detection of NADP*H - diaphorase. Discussion results: There were registered small number of fos-\m mu no reactive nuclei in C6/C7 segments of spinal cord of animals. The designated neurons were found in different layers of the gray matter, but in the motor nuclei (layer 9) and in the lateral spinal nuclei (LSp) fos immunoreactivity was registered in few number of cells. Cells containing c-Fos protein and NOsynthase are simultaneously identified as double staining neurons. Conclusion: The results of research of spatial and quantitative characteristics distribution of motoneurons and interneurons that were activated in the cervical part of spinal cord of rats after repeated realizations of food extractive movements are presented in this work.