ABSTRACT
OBJECTIVE@#To discuss the effect of Yaobitong capsule on histomorphology of dorsal root ganglion and on expression of p38MARK phosphorylation in autologous nucleus pulposus transplantation model of rats.@*METHODS@#A total of 60 SD rats were randomly divided into the blank group, model group and Yaobitong capsule group, with 20 rats in each group. The animal model of autologous nucleus pulposus transplantation around the lumbar nerve root was built. Three days after the modeling, rats were given the drugs for the first time, while rats in the model group were given the equivalent normal saline. After 30 d of continuous administration, samples were collected from rats. HE staining was performed on the dorsal root ganglion of L4 and L5 spinal cord of rats in each group and the expression of p38MARK phosphorylation was measured. All data were treated with the statistical analysis.@*RESULTS@#The histological examination showed that the histomorphology of dorsal root ganglion in the Yaobitong capsule group was more significantly improved than the one in the model group, while the results of western blot showed that Yaobitong capsule could significantly inhibit the level of p38MAPK phosphorylation of dorsal root ganglion cells.@*CONCLUSIONS@#Yaobitong capsule can improve the symptoms and nerve radiculopathy of autologous nucleus pulposus transplantation of rats and its mechanism may be associated with its inhibiting effect on the level of p38MAPK phosphorylation.
ABSTRACT
Objective: To discuss the effect of Yaobitong capsule on histomorphology of dorsal root ganglion and on expression of p38MARK phosphorylation in autologous nucleus pulposus transplantation model of rats. Methods: A total of 60 SD rats were randomly divided into the blank group, model group and Yaobitong capsule group, with 20 rats in each group. The animal model of autologous nucleus pulposus transplantation around the lumbar nerve root was built. Three days after the modeling, rats were given the drugs for the first time, while rats in the model group were given the equivalent normal saline. After 30 d of continuous administration, samples were collected from rats. HE staining was performed on the dorsal root ganglion of L4 and L5 spinal cord of rats in each group and the expression of p38MARK phosphorylation was measured. All data were treated with the statistical analysis. Results: The histological examination showed that the histomorphology of dorsal root ganglion in the Yaobitong capsule group was more significantly improved than the one in the model group, while the results of western blot showed that Yaobitong capsule could significantly inhibit the level of p38MAPK phosphorylation of dorsal root ganglion cells. Conclusions: Yaobitong capsule can improve the symptoms and nerve radiculopathy of autologous nucleus pulposus transplantation of rats and its mechanism may be associated with its inhibiting effect on the level of p38MAPK phosphorylation.
ABSTRACT
OBJECTIVE: To observe the long-lasting changes of pain progression with time course in an autologous nucleus pulposus model of rat. METHOD: The subjects were 25 Sprague-Dawley (Sprague- Dawley, 250 gm) male rats. They were randomly assigned into either the sham or experimental group. In the experimental group (n=15), autologous nucleus pulposus was harvested from the coccygeal intervertebral disc of the rat and this was grafted on the left L5 dorsal root ganglion. In the sham group (n=10), the left L4 and L5 nerve roots were exposed by laminectomy, but the nucleus pulposus was not grafted. All the rats were evaluated for mechanical allodynia and thermal hyperalgesia at 2 days before surgery, and on days 1, 5, 10, 20, 30, 40 and 50 after surgery. The morphological changes of the spinal nerves were assessed by toluidine blue staining on days 5 after surgery. RESULTS: In the ipsilateral hindpaw of the experimental group, there was a dramatic drop of the mechanical withdrawal threshold and the thermal withdrawal latency on day 1 after surgery, which was maintained at day 50 after surgery. In morphological study, pathological findings such as swelling of the myelin sheath, demyelination, swelling and degeneration of the axoplasm were observed in the spinal nerve at day 5 after surgery. CONCLUSION: The long-lasting pattern of neuropathic radicular pain shown in a rat model of lumbar disc herniations is helpful to understand the natural history of neuropathic radicular pain due to ruptured nucleus pulposus.
Subject(s)
Animals , Humans , Male , Rats , Demyelinating Diseases , Ganglia, Spinal , Hyperalgesia , Intervertebral Disc , Laminectomy , Myelin Sheath , Natural History , Salicylamides , Spinal Nerves , Tolonium Chloride , TransplantsABSTRACT
Objective To observe the morphologic changes of dorsal root ganglion in the lumbar region of rabbits after the nerve root was under chronic compression and inflammatory stimulation. Methods Twenty New Zealand rabbits were recruited for this study, of which 5 served as the control (control group), and the rest were randomized into 3 experimental subgroups: 10d group, 30d group, 90d group, respectively. The autologous nucleus pulposus from the tails (about 5mg) was put into the silastic tube (inner meter of 1.5mm, external diameter 2.5mm and length 12mm), which was inserted into the left L 7 intervertebral foramen to compress the lumbar nerve root. Sham operation was performed with the rabbits in the control group. The nerve root and the dorsal root ganglia were harvested and processed and observed with light microscope and electron microscope after 10d, 30d, 90d, respectively. Results In the 10d group, obvious hyperemia, edema and infiltration of inflammatory cells in the interspace of the intima of the dorsal root ganglia (DRG) could be observed. Pyknosis, degeneration and necrosis were also found in some of the nerve cells. Electron microscopic observation showed that the number of the rough endoplasmic reticulum and mitochondrion decreased, ribosome exfoliated, mitochondrion swelled. In 30d group, typical degeneration and necrosis became more obvious. Electron microscope showed that the number of lysosome and smooth endoplasmic reticulum increased, mitochondrion swelled and its cristae disappeared, nuclei concentrated and deviated. In 90d group, significant proliferation of fibrocyte could be observed. At the same time, dura mater and arachnoid of spinal cord around the nerve root were notably thickened, and became fibrogenesis. Electron microscope also showed the increment of the lysosome and smooth endoplasmic reticulum, the swelling of mitochondrion, the loss of its cristae and the concentration of the nucleolus in the central part of the nuclei. No significant changes were found in the control group. Conclusion Pathological changes of neural degeneration such as edema, inflammatory infiltration could be observed in dorsal root ganglion after the nerve root was under chronic compression and stimulation by autologous nucleus pulposus.