The time-dependent expression of α7nAChR during skeletal muscle wound healing in rats.
The study on time-dependent expression of α7 nicotine acetylcholine receptor (α7nAChR) was performed by immunohistochemistry, Western blotting, and real-time PCR during skeletal muscle wound healing in rats. Furthermore, co-localization of α7nAChR with macrophage or myofibroblast marker was detected by double immunofluorescence. A total of 50 Sprague-Dawley male rats were divided into control and contusion groups (3 h, 6 h, 12 h, 1 day, 3 days, 5 days, 7 days, 10 days, and 14 days post-injury). In the uninjured controls, α7nAChR positive staining was observed in the sarcolemma and sarcoplasm of normal myofibers. In wounded specimens, a small number of polymorphonuclear cells, a number of macrophages and myofibroblasts showed positive reaction for α7nAChR in contused zones. Morphometrically, the average ratios of α7nAChR-positive cells were over 50 % from 3 to 10 days after contusion, and exceeded 60 % at 5 and 7 days post-injury. Besides, the positive ratios of α7nAChR were <50 % at the other posttraumatic intervals. By Western blotting analysis, the average ratio of α7nAChR protein expression maximized at 7 days after injury, which was >2.13. Similarly, the relative quantity of α7nAChR mRNA expression peaked at 7 days post-wounding as compared with control by real-time PCR detection, showing a relative quantity of >2.65. In conclusion, the expression of α7nAChR is upregulated and temporally distributed in macrophages and myofibroblasts during skeletal muscle wound healing, which might be closely involved in inflammatory response and fibrotic repair after injury. Moreover, α7nAChR is promising as a useful marker for wound age determination of skeletal muscle.
Department of Forensic Medicine, School of Basic Medical Science, Wenzhou Medical University, Wenzhou, Zhejiang Province, 325035, People's Republic of China, yyfan998@163.com.
Yan-Yan
YY
Fan
Shu-Tao
ST
Zhang
Lin-Sheng
LS
Yu
Guang-Hua
GH
Ye
Ke-Zhi
KZ
Lin
Shu-Zhen
SZ
Wu
Miao-Wu
MW
Dong
Jun-Ge
JG
Han
Xiang-Ping
XP
Feng
Xing-Biao
XB
Li
D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D003288:Contusions / Q000378:metabolism*; D049429:Forensic Pathology; D007150:Immunohistochemistry; D008264:Macrophages / Q000378:metabolism*; D023421:Models, Animal; D018482:Muscle, Skeletal / Q000293:injuries / Q000378:metabolism*; D058628:Myofibroblasts / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D017207:Rats, Sprague-Dawley; D060888:Real-Time Polymerase Chain Reaction; D013194:Staining and Labeling; D013997:Time Factors; D015854:Up-Regulation; D014945:Wound Healing / Q000502:physiology*; D064569:alpha7 Nicotinic Acetylcholine Receptor / Q000235:genetics / Q000378:metabolism*
D015415:Biomarkers; D012333:RNA, Messenger; D064569:alpha7 Nicotinic Acetylcholine Receptor