Chemokine CCL21 in anterior cingulate cortex is involved in chronic neuropathic pain in a rat model
10.3969/j.issn.2095-4344.2982
- Author:
Yibo ZHI
1
Author Information
1. Southern Medical University
- Publication Type:Journal Article
- Keywords:
Anterior cingulate cortex;
CCL21;
Chemotactic factor;
Chronic pain;
Ligation of infraorbital nerve;
Microglia;
Pathological
- From:
Chinese Journal of Tissue Engineering Research
2021;25(2):242-246
- CountryChina
- Language:Chinese
-
Abstract:
BACKGROUND: The pathogenesis of chronic pathological pain is yet unknown. Some studies have shown that after spinal cord injury, CCL21 can activate microglia in the central nervous system and is expressed only in damaged neurons, promoting the formation of chronic pathological pain. OBJECTIVE: To investigate whether the anterior cingulate cortex is involved in the formation of chronic pathological pain after inferior orbital nerve ligation in rats, and whether blocking chemokine CCL21 in the anterior cingulate cortex can reduce the chronic neuropathic pain. METHODS: A total of 80 male Sprague-Dawley rats were randomly divided into 4 groups with 20 rats in each group. In the sham group, only the infraorbital nerve of the rats was exposed; in the model group, the left infraorbital nerve was ligated; in the anti-CCL21 group, CCL21 neutralizing antibodies was administered to the anterior cingulate cortex of the rats on the 7th day after surgery; and in the PBS control group, PBS solution was given into the anterior cingulate cortex of rats on the 7th day after surgery. Rats in the sham and model groups were subjected to behavioral tests on the 3rd, 5th, 7th, and 14th days after surgery, and those in the anti-CCL21 and PBS control groups were subjected to the behavioral test at 6 hours after administration. All rats were sacrificed under anesthesia after behavioral tests. The cortical tissues were taken from the anterior cingulate, and the protein content of CCL21 was determined by western blot and immunofluorescence. RESULTS AND CONCLUSION: The pain threshold of the rats in the model group was lower than that in the sham group, and the expression of CCL21 in the anterior cingulate cortex was significantly higher in the model group than the sham group. After the administration of CCL21 neutralizing antibody, the expression of CCL21 was reduced to some extents, and the rat pain threshold was increased accordingly. These findings reveal that the anterior cingulate cortex of rats may be involved in the production of chronic pathological pain, and the administration of CCL21 neutralizing antibody can relief the pain.
