ABSTRACT
Purpose To study the relationship between sympathetic nerve and the branches of primary sensory neurons in dominating cervical zygapophyseal joints with the HRP retrograde tracing methods.To explore the mechanism of the external intervertebral foramen's cryical nerve compression syndrome with neck-shoulder pain and the symptom of head and face regions. Methods 8 Wistar rats were used with the right side as experimental side and the left side as control side.5 μl of 30% HRP solution was injected into the C5/C6 cervical zygapophyseal joint capsule of the right side by microinjection syringe and 5 μl of 0.9% normal saline was injected into the left side as control.The animals survived for 48 hours and were killed by perfusing through ascending aorta.The C1-T1 DRG,cervical sympathetic ganglia and trigeminal ganglia on both sides were sectioned by frozen section method,and treated with TMB method.The HRP labeled cells in sections were observed under optical microscope.The classification and count of HRP labeled cells in DRG and cervical sympathetic ganglia on experimental sides were analysed by image pattern analysis system. Results There were HRP labeled cells in middle cervical ganglia,inferior cervical ganglia (stellate ganglia) and C5-C7 DRG on experimental sides after HRP injection.Most of the labeled cells were small or middle size.The sum of mean area and the mean optical density of HRP labeled cells were larger in the middle cervical ganglia and C6 DRG than that in inferior cervical ganglia(stellate ganglia) and C5 or C7 DRG separately (P<0.01).There wasn't any HRP labeled cell in C1-T1 DRG of control side and in trigeminal ganglia. Conclusions The cervical zygapophyseal joint mainly dominated by the sensory branches of the three cervical nerves next to it and by the branches of the sympathetic nerves.It may be related to the causing of neck-shoulder pain and the symptoms of head and face regions of patients with the external intervertebral foramen's cervical nerve compression
ABSTRACT
Objective To understand the base of the neuroanatomy underlying the nociceptive syndrome occurring in cervical zygapophyseal joints,in which pain in upper limb was accompanied. Methods The capsules of the C4-T1 zygapophyseal joints of SD rats were immunostained with anti-calcitonin-gene-related peptide(CGRP) antibody,and a modified tricetry labeling was done as following:the fluorescents,fast blue(FB) and nucleus yellow(NY),were injected,respectively,into the right radial nerve and capsules of the zygapophyseal joints of neck,then, the ipsilateral dorsal root ganglia(DRG) were sectioned and the retrogradely labeled sensory neurons in the DRG were observed and photographed,finally,the sections were further immunostained with anti-CGRP antibody,eventually,the neurons in both of the photos labeled by fluorescents and anti-CGRP antibody were comparatively observed and analyzed. Results The nervers fibers containing CGRP distributed throughout the capsules of the zygapophyseal joints from C4-T1 in the rat.Most of these fibers coursed straightly and individually,and some of them anastomosed to each other to form the networks of the nerve fibers.The neurons retrograde labeled by fluorescents were observed in each of the DRG from C5-T1.These neurons shared a labeling populations of FB single(76%),NY single(16%) and FB/YN double labeling(8%) respectively.Moreover, about 40% fluorescents labeled neurons were immunoreacted to CGRP.Conclusion The peripheral processes from a population of sensory neurons that contain CGRP in the cervical DRG simultaneously innervated both the capsules of cervical zygapophyseal joints and the fore limb with the radial nerve.The present results suggest that the nociceptive syndrome of cervical zygapophyseal joints with pain in human upper limb might be the referred pain occurring in the level of the DRG.