TY - JOUR
T1 - Expression of acetylated histone 3 in the spinal cord and the effect of morphine on inflammatory pain in rats
AU - Li, Hua
AU - Li, Changqi
AU - Dai, Ru-Ping
AU - Shi, Xu
AU - Xu, Junmei
AU - Zhang, Jian
AU - Zhou, Xin-Fu
AU - Li, Zhiyuan
AU - Luo, Xue-Gang
PY - 2012/3
Y1 - 2012/3
N2 - In this study, a rat model of inflammatory pain was produced by injecting complete Freund's adjuvant into the hind paw, and the expression of acetylated histone 3 in the spinal cord dorsal horn was examined using immunohistochemical staining. One day following injection, there was a dramatic decrease in acetylated histone 3 expression in spinal cord dorsal horn neurons. However, on day 7, expression recovered in adjuvant-injected rats. While acetylated histone 3 labeling was present in dorsal horn neurons, it was more abundant in astrocytes and microglial cells. The recovery of acetylated histone 3 expression was associated with a shift in expression of the protein from neurons to glial cells. Morphine injection significantly upregulated the expression of acetylated histone 3 in spinal cord dorsal horn neurons and glial cells 1 day after injection, especially in astrocytes, preventing the transient downregulation. Our results indicate that inflammatory pain induces a transient downregulation of acetylated histone 3 in the spinal cord dorsal horn at an early stage following adjuvant injection, and that this effect can be reversed by morphine. Thus, the downregulation of acetylated histone 3 may be involved in the development of inflammatory pain.
AB - In this study, a rat model of inflammatory pain was produced by injecting complete Freund's adjuvant into the hind paw, and the expression of acetylated histone 3 in the spinal cord dorsal horn was examined using immunohistochemical staining. One day following injection, there was a dramatic decrease in acetylated histone 3 expression in spinal cord dorsal horn neurons. However, on day 7, expression recovered in adjuvant-injected rats. While acetylated histone 3 labeling was present in dorsal horn neurons, it was more abundant in astrocytes and microglial cells. The recovery of acetylated histone 3 expression was associated with a shift in expression of the protein from neurons to glial cells. Morphine injection significantly upregulated the expression of acetylated histone 3 in spinal cord dorsal horn neurons and glial cells 1 day after injection, especially in astrocytes, preventing the transient downregulation. Our results indicate that inflammatory pain induces a transient downregulation of acetylated histone 3 in the spinal cord dorsal horn at an early stage following adjuvant injection, and that this effect can be reversed by morphine. Thus, the downregulation of acetylated histone 3 may be involved in the development of inflammatory pain.
KW - Acetylated histone 3
KW - Hyperalgesia
KW - Inflammation
KW - Morphine
KW - Neurobiology
KW - Spinal cord
UR - http://www.scopus.com/inward/record.url?scp=84861219411&partnerID=8YFLogxK
M3 - Article
SN - 1673-5374
VL - 7
SP - 517
EP - 522
JO - Neural Regeneration Research
JF - Neural Regeneration Research
IS - 7
ER -