School of Chinese Medicine
Aims: Recent studies suggested that the development of neuropathic pain associated with neural injury may be partly due to up-regulation of cyclooxygenase (COX) in the central nervous system. However, the cellular sources of COX-1 and COX-2 up-regulation following nerve injury are unclear. Methods: We investigated the spinal cellular sources of COX-1 and COX-2 in association with allodynia following L5 spinal nerve ligation (SNL). Results: Post-SNL pain-related behaviour was shown by increased sensitivity to mechanical stimulation. There was a significant increase in both COX-1 and COX-2 immunoreactivity (P < 0.01) on the ipsilateral side of spinal dorsal horn. Double immunofluorescence labelling demonstrated that COX-1 immunoreactive cells colocalized chiefly with dorsal horn neuronal nuclei and microglia, whereas COX-2 was expressed in neuronal cytoplasm. Conclusion: These findings demonstrate that while spinal dorsal horn neurones are important source of COX-1 and COX-2 after nerve injury, microglia also contribute to the pathogenesis of neuropathic pain, partly by producing additional COX-1. © 2013 British Neuropathological Society.
Astrocyte, COX, Microglia, Neurone, Neuropathic pain, Spinal cord
Source Publication Title
Neuropathology and Applied Neurobiology
This is the peer reviewed version of the following article: Lau, Y. M., Wong, S. C., Tsang, S. W., Lau, W. K., Lu, A. P. and Zhang, H. (2014), Cellular sources of cyclooxygenase-1 and -2 up-regulation in the spinal dorsal horn after spinal nerve ligation. Neuropathol Appl Neurobiol, 40: 452–463. doi:10.1111/nan.12078, which has been published in final form at http://dx.doi.org/10.1111/nan.12078. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.
Supported by Hong Kong Baptist University FRG05-06/ II-55 & FRG/04-05/I-16, and SCM postdoctoral fellowship. We thank Nickie Chan for her invaluable technical support.
Link to Publisher's Edition
Lau, Yee Man, Shing Chau Wong, Sin Wah Tsang, Wai Kit Lau, Ai Ping Lu, and Hongqi Q. Zhang. "Cellular sources of cyclooxygenase-1 and -2 up-regulation in the spinal dorsal horn after spinal nerve ligation." Neuropathology and Applied Neurobiology 40.4 (2014): 452-463.