Research on the Mechanism of Pain and Negative Emotion in Cold-Dampness-Type Lumbar Disc Herniation

OBJECTIVE To investigate the potential mechanism of pain and negative emotion in cold-dampness-type lumbar disc herniation (LDH). METHODS 23 cases of LDH operation were collected. According to the dialectical standard of Chinese medicine， the patients were divided into cold dampness group and non cold dampness group， 11 and 12 serum samples were respectively obtained， 11 and 7 of the diseased intervertebral discs were respectively collected. The serum samples of 10 healthy persons were collected as normal group. The levels of serum interleukin-1β (IL-1β)， tumor necrosis factor-α (TNF-α)， 5- serotonin (5-HT)， calcitonin related gene peptide (CGRP)， neuropeptide Y (NPY)， β-endorphin (β-EP)， P substance (SP) were detected by ELISA. The qPCR and Western blot were used to detect the mRNA and protein expression of 5-HT， CGRP， NPY and β-EP in diseased intervertebral discs. RESULTS Compared with the non cold dampness group， there was no significant difference in age， course of disease， pain and numbness score in cold dampness group， but the score of insomnia and anxiety increased significantly (P<0.05). Serological test showed that there was a common trend of significant decrease of CGRP and significant increase of NPY (P<0.01) in both the cold dampness group and the non cold dampness group compared with the normal group， while the β-EP in the cold dampness group was also significantly increased (P<0.01). Compared with the non cold dampness group， the CGRP decreased in the cold dampness group (P<0.05)， and the β-EP increased significantly (P<0.01). Compared with the non cold dampness group， the expression of CGRP mRNA and protein increased in the cold dampness group (P<0.05)， and the expression of β-EP mRNA and NPY protein decreased (P<0.05) in the cold dampness group. CONCLUSION Compared with the non cold dampness syndrome， the cold-dampness LDH has a closer relationship between pain and negative emotions. CGRP， NPY， and β-EP were differentially expressed in peripheral blood and diseased intervertebral discs， suggesting that these factors play a important role in mediating pain and negative emotions.