Objective:To observe the influence of high intensity focused ultrasound(HIFU)damaging the celiac ganglion(CG) of rabbits on expression of c-fos in spinal cord following gastric distension

and study the potential mechanism in treating pain. Mothods:20 healthy and grown New Zealand rabbits were randomly divided into four groups: not distend damage(nDB)

distend damage(DB)

not distend not damage(nDnB)

distend not damage(DnB)

with 5 in each group. At first

the CG was exposed under aseptic manipulation

then group nDB and DB were damaged by HIFU

group nDnB and DnB not damaged. 7 days later

they all were installed with the device of gastric distension under anaesthesia. In group nDB and nDnB tissue were directly fixed through infusing 4% parafomaldehyde under deep anaesthesia

then spinal cord of thoracic 6~8(T6~8)extracted. In group DB and DnB stomach was distended step by step. Repeat distension for 1h

the spinal cord were extracted in the way similar to that the above two groups. The number of fos-like immunoractivity neurons(FLIN) in spinal cord was displayed using immunohistochemistry technique of Strept Avidin Biotin Complex(SABC). Results:Damaged CG and gastric distension as well as damaged CG combined with gastric distension could not induce the FLIN in dorsal horn as well as the anterior gray horn of thoracic slices to significantly increase(P>0.05). Conclusion:HIFU damaging the celiac plexus(CG) has no influence on expression of c-fos in spinal cord of gastric distension rabbits. This is different from the expression of c-fos in spinal cord caused by other visceral nerves being damage of nociceptive stimulus

which might relate to the special central mechanism of modulating nociceptive signal for stomach.