[Impact of acupuncture to IGF-I expression in spared dorsal root ganglion of cats].
OBJECTIVE
To explore the relationship between Insulin-like growth factor-I (IGF-I) and acupuncture promoting the spinal cord plasticity, the changes of IGF- I expressing in spared dorsal root ganglia (DRG,L6) after operation and acupuncture were investigated.


METHODS
25 adult cats were divided into 5 groups: normal control group; 7th day and 14th day group after unilateral partial rhizotomy (unilateral L1-L5,L7-S2 DRG Were transected, but L6 DRG was spared); 7th day and 14th day group of acupuncture stimulating the spared DRG (electro-needle stimulation was performed by following unilateral partial root rhizotomy). Animals survived for 7 or 14 days after operation respectively. Unilateral L6 dorsal root ganglia of each group were made into 20 microm frozen sections. By immunohistochemistry ABC method, the sections were stained with specific IGF-I (1:200) antibody. The distribution and the number of IGF-I positive neurons in spared DRG (L6) that located the operated/acupuncture side of each animal were observed and counted.


RESULTS
For 7th day group after acupuncture stiumlation, the number of IGF-I positive neurons of spared DRG of acupuncture side showed significantly more than that of 7th day operation group (P<0.05), but still less than that of normal group (P < 0.05); In 14th day group, IGF- I expression in neuron of L6 DRG also increased apparently more than that of 14th day operation group, with coming back to normal level. After acupuncture stimulating the spared DRG for 14 days, the numbers of IGF- I positive neurons in spared DRG increased significantly more than that of 7th day group after acupuncture (P<0.05).


CONCLUSIONS
Acupuncture can significantly increase the number of IGF- I positive neurons. Our results indicate that the expression changes of IGF-I in spared DRG associate with acupuncture promoting the spinal cord plasticity.
Liu
Fen
F
Department of Histology and Embryology, Wenzhou Medical College, Wenzhou 325035, China.
Wang
Ting-Hua
TH
Zhang
Yi
Y
Hong
Sun-quan
SQ
Song
Xin-bo
XB
D026881:Acupuncture; D015669:Acupuncture Points; D000818:Animals; D002415:Cats; D015671:Electroacupuncture; D005727:Ganglia, Spinal / Q000378:metabolism*; D007334:Insulin-Like Growth Factor I / Q000096:biosynthesis* / Q000235:genetics; D008297:Male; D009473:Neuronal Plasticity / Q000502:physiology*; D009474:Neurons / Q000378:metabolism; D011897:Random Allocation; D019051:Rhizotomy; D013116:Spinal Cord / Q000166:cytology / Q000378:metabolism*
D007334:Insulin-Like Growth Factor I