肝细胞生长因子在防治大鼠腓肠肌废用性萎缩中的作用

Effects of hepatocyte growth factors on contractile function of disused gastrocnemius atrophy in rats

目的观察肝细胞生长因子(HGF)对大鼠后肢(石膏固定4周后)的腓肠肌湿重及收缩功能的影响,探讨其在大鼠废用性骨骼肌萎缩防治中的作用。方法选用雄性Wistar大鼠24只,随机分为空白组(8只)、对照组(8只)和实验组(8只)。空白组不予任何处理,笼中自由活动。按照Jozsa等的方法,将对照组和实验组大鼠右后肢用可塑性石膏由足跖管型固定至膝上1 cm处,膝关节固定于屈曲位100°,踝关节固定于跖屈60°位,共4周。固定当天开始,实验组每人予HGF腓肠肌注射(剂量：10 mg/kg,浓度：10 mg/mL),1次/ d,共注射28 d；对照组每天予等量生理盐水腓肠肌注射。4周后完整解剖右后肢腓肠肌,检测腓肠肌湿重及收缩功能。结果对照组、实验组与空白组相比,腓肠肌湿重、单次收缩最大张力、强直收缩最大张力显著下降,差异有显著性意义(P＜0．05),产生收缩、单次最大收缩和最大强直收缩的域值均显著下降,差异有显著性意义(P＜0．05)。实验组的腓肠肌湿重、单次收缩最大张力、强直收缩最大张力均优于对照组,差异有显著性意义(P＜0．05),产生收缩、单次最大收缩和最大强直收缩的刺激强度均显著高于对照组,差异有显著性意义(P＜0．05)。结论局部注射HGF能显著提高大鼠废用性萎缩腓肠肌的收缩功能和肌肉湿重,对防治骨骼肌的废用性萎缩有明显效果。

Objective To explore the possible effects of hepatocyte growth factors （HGF） on prevention and therapy of disused gastrocnemius atrophy in rats by observing their effects on the wet weight and contractile function of the gastrocnemius of fixed hind limbs. Methods Twenty-four Wister male rats were randomly divided into a blank group, a contrast group and an experimental group. Their fight hind limbs were fixed for four weeks with plastic plaster from metatarsus to 1 cm up the knee. Their knee joint was fixed in 100° flexion and their ankle joint in 60° plantar flexion. Rats in the contrast group were injected with 0.2 mL of normal saline, and rats in the experimental group were injected with HGF （10 mg/kg, 10 mg/mL） . Their whole gastrocnemius of the fight hind limb was dissected four weeks later to measure its contractile function and wet weight. Results Compared with the blank group, single maximal contraction, maximal tetanus, and wet weight of the gastrocnemius in the contrast and experimental groups decreased significantly （ P 〈 0. 05 ）, and fields of electric stimulation also decreased significantly （ P 〈 0.05 ） . Compared with the contrast group, single maximal contraction, maximal tetanus, and wet weight of the gastrocnemius in the experimental group were significantly superior （ P 〈 0. 05 ）, and fields of electric stimulation significantly increased. Conclusion Since after a local injection of HGF, the contractile function and wet weight can be significantly increased, HGF may have a preventive effect on disused atrophy.