Study Design. Cumpression-induced changes in the concantration of substance P and VIP (vasoactive intestinal polypeptide), in spinal nerve roofs ami dorsal root ganglia were studied ir an experimental nerve root compassion model in pigs. Objectives. To analyze by radioimmunaassay the concentration of the neuropeptides substance P and VIP in a model for experimental chronic nerve root compression. Summary of Background Data. Nourapeptides such as substance F and VIP seem to be involved in the transmission of pain and changes in the levels of these neuropeptides have been described in models where peripheral or spinal nerve Iniury was Induced. Methods. An ameroid constrictor was applied on a spinal nerve root just cranial to the dorsal rool ganglion. The inner diameter of this constrictor is gradually reduced, After 1 or 4 weeks, Tissue samples were taken from the nerve root cranial to the constrictor and from the dorsal foot ganglion for measurement of substance P and VIP concentrations. Results. There was a statistically significant increase in substance P concentrations in the compressed dorsal root ganglla when compared to the noncompressed dorsal root ganglia at both 1 and 4 weeks, Substance P concentration was also Significantly increased In the nerve root after 1 but not after 4 weeks. The VIP levels wcru not Significantly changcd in either tiasuo. Conclusions. The results of the study indicates an increase in substance P level in the dorsal root ganglion (after 1 and 4 weeks) and in the nerve root (after 1 weeks) in a model for chronic nerve root compression In pigs. There were no significant differences in the VIP concentrations. The sliidy thus indicates that changes in substance P ere related to experimental chronic nerve root compression.
- Norve rosis
- Sciatine substance P
- Vbso active inies-tmal polypeptide
ASJC Scopus subject areas
- Orthopedics and Sports Medicine
- Clinical Neurology