title: Upgraded nerve growth factor expression induced by low-intensity continuous-wave ultrasound accelerates regeneration of neurotometicly injured sciatic nerve in rats.
abstract: Low-intensity ultrasound (LIU) can stimulate injured nerve regeneration but the mechanism is still unclear. We investigated the stimulating effect and its mechanism of continuous-wave LIU on neurotometic injury of sciatic nerve. The right sciatic nerves of 64 adult Wistar rats were first crushed and then exposed (32 rats) or sham-exposed (32 rats) to LIU at the crush site. The LIU had a spatial averaged and temporal averaged intensity of 0.25 W/cm(2) operated at 1.0 MHz for 1 min every other day. At various stages (the second, fourth, sixth and eighth weeks) after LIU exposure, the sciatic nerve function index (SFI), the sensory nerve conduction velocity (SNCV), the expression of nerve growth factor (NGF) and sample histology were studied. It was found that the density of nerve fibers with myelin sheath, SFI, SNCV and NGF expression of the treatment group were higher than that of control group (p < 0.05). It has been determined that LIU treatment can accelerate the regeneration and functional recovery of neurotometic injured sciatic nerve at earlier stages after injury, the upgraded expression of NGF induced by LIU may be the primary mechanism of the acceleration effects.
authors.affiliation: Institute of Ultrasonic Engineering in Medicine, Chongqing Key Laboratory of Ultrasound Medical Engineering, Chongqing Medical University, Chongqing, China.
authors.forename: Wen-Zhi
authors.initials: WZ
authors.lastname: Chen
authors.forename: Hai
authors.initials: H
authors.lastname: Qiao
authors.forename: Wei
authors.initials: W
authors.lastname: Zhou
authors.forename: Junru
authors.initials: J
authors.lastname: Wu
authors.forename: Zhi-Biao
authors.initials: ZB
authors.lastname: Wang
mesh_terms: D000818:Animals; D005260:Female; D020932:Nerve Growth Factor / Q000378:metabolism*; D009416:Nerve Regeneration / Q000528:radiation effects*; D009431:Neural Conduction / Q000528:radiation effects*; D051381:Rats; D017208:Rats, Wistar; D020426:Sciatic Neuropathy / Q000503:physiopathology* / Q000628:therapy*; D015398:Signal Transduction / Q000528:radiation effects*; D016896:Treatment Outcome; D014464:Ultrasonic Therapy / Q000379:methods*; D015854:Up-Regulation / Q000528:radiation effects
chemical_list: D020932:Nerve Growth Factor