睫状神经营养因子对大鼠去神经骨骼肌的营养作用

TROPHIC EFFECT OF CILIARY NEUROTROPHIC FACTOR ON DENERVATED SKELETAL MUSCLE

目的 :了解睫状神经营养因子 (CNTF)对去神经引起的肌肉萎缩的治疗作用。方法 :离断SD大鼠一侧坐骨神经 ,连续给予CNTF 2 0d ,观察肌肉湿重、蛋白含量、肌纤维横截面积、收缩性能和肢残程度。结果 :①给予 0 .2mg/kg的CNTF ,可使损伤侧肌纤维横截面积增加 35 % ,肌肉湿重增加 38% ,胫前肌总蛋白含量增加 2 4% ,腓长肌强直收缩强度提高 40 % ,显著改善肢残程度 ;② 0 .2mg/kg的CNTF作用明显强于 0 .0 5mg/kg的CNTF ;③比目鱼肌(慢肌 )比伸趾长肌 (快肌 )对CNTF更敏感。结论 :CNTF能显著改善成年大鼠坐骨神经离断后骨路肌的萎缩和功能丧失 。

Aim: The trophic effect of CNTF on skeletal muscle atrophy and dysfunction reduced by denervation was investigated in SD rats. Methods: SD rats transected sciatic nerve in right side hind limbs were injected CNTF subscutaneously for 20 days. Skeletal muscle wet weights, protein contents, muscle fiber cross-sectional areas, contract properties and degree of hind limb abnormalities were observed in the rats. Results: ①Administrating CNTF (0.2 mg/kg) in sciatic nerve transected SD rats attenuated denervation induced skeletal muscle fiber atrophy evidently, resulted in gastrocnemius in injury side an obvious increase in contract function, prevented the loss of weights and protein in denervated skeletal muscle, and ameliorated abnormalities in sciatic nerve cut limbs remarkably. ②The myotrophic effect of 0.2 mg/kg CNTF is more effective than 0.05 mg/kg. ③The sensitivity to CNTF varied in muscles of different type; slow twitch muscle (soleus muscle) reacted to CNTF stronger and quicker than twitch muscle (extensor digitorum longus). Conclusion: CNTF significantly attenuates denervation reduced skeletal muscle atrophy and dysfunction in SD rats, act an evident myotrophic effect on denervated skeletal muscle. And this effect may be exerted in a dosage dependent manner and varies with muscle type.