Characterization of thermal XXXX , @entity5019 expression, and alterations in neuropeptides after mechanical irritation of the dorsal root ganglion.

@entity1 @entity1931 @entity5019 @entity13549 @entity158 @entity35
STUDY DESIGN: This study analyzed hypersensitization in sensory systems after mechanical irritation of the dorsal root ganglion. OBJECTIVES: To develop a reliable and reproducible animal model of @entity1931 arising from the dorsal root ganglion and to understand the unique contributions of the dorsal root ganglion to clinical manifestations of @entity13549 . SUMMARY OF BACKGROUND DATA: The dorsal root ganglion likely plays an important role in disorders of @entity13549 . However, no previous study has analyzed @entity13549 after irritation of the dorsal root ganglion. Thermal @entity1931 indicates a decrease in thermal nociceptive threshold and hypersensitization in sensory systems. METHODS: The left L4 and L5 dorsal root ganglia in @entity35 (n = 22) were exposed circumferentially. Other @entity35 (n = 22) also had the left L4 and L5 dorsal root ganglia ligated loosely with two 4-0 chromic gut sutures. Changes in thermal withdrawal latency were examined in the hindpaws across time. Substance P and vasoactive intestinal polypeptide contents were quantified in the dorsal root ganglion and spinal cord. Substance P, calcitonin gene-related peptide, and @entity5019 expression also were examined in the spinal cord by immunohistochemistry. In addition, histologic changes in myelinated nerve content were examined in the dorsal root ganglion. RESULTS: Thermal @entity1931 occurred in @entity35 with exposure of the dorsal root ganglion and in @entity35 with loose ligation of the dorsal root ganglion, and was accompanied by an increase in @entity5019 expression and spontaneous @entity158 . CONCLUSIONS: This experimental model reliably produced a disorder resembling an acute phase @entity13549 and should help further advance the understanding of pathomechanisms of @entity158 after irritation of the dorsal root ganglion in @entity1 .
