PLASMA CONTENT OF β ENDORPHIN IN PATIENTS WITH ACUTE ABDOMINAL DISEASE OR CHRONIC SPINAL NEURALGIA
ZHANG Jin Shan 1, FENG Jin Hua 1, AN Jian Xiong 2, LUO Fei 2, JIN Shu Ming 1, LI Zhong Lian 1 1 Pain Clinic Center, Tianjin First Hospital 300010 2 Sino French Pain Center, Beijing Medical University, Beijing 100083
To investigate the relationship between plasma content of β endorphin and acute or chronic pain, we collected blood samples from randomly selected patients with acute abdominal disease or chronic spinal neuralgia before and after treatment. The content of β endorphin levels in these samples were determined by radioimmunoassay. The result was compared with those of normal volunteers. (1) Plasma contents of β endorphin in patients with acute abdominal disease were slightly higher than normal, however, this difference was not statistically significant. β endorphin level decreased by 20% after the treatment, but this was again statistically not significant. (2) Plasma β endorphin content in chronic spinal neuralgia patients were significantly lower than normal (P0.001). Although the 11 point numeric rating scale (NRT 11) pain score of these patients decreased significantly after treatment (from 8.46±0.29 to 3.92±0.37, P0.01), the average plasma content of β endorphin showed only slight decrease without statistical difference. (3) The decrease of pain scores after treatment showed a significant correlation with the decrease of plasma β endorphin contents (r=0.64, P0.05) in patients with chronic spinal neuralgia. We suggest that the lowered plasma β endorphin content might be one of the important factors for the development of pain in patients with chronic spinal neuralgia. The plasma β endorphin may play a role in anti nociceptive action.