低氧高糖条件下家兔骨骼肌Ⅰ型纤维向Ⅱ型纤维转化的作用

Effect of low oxygen and high glucose on skeletal muscle Ⅰ type fiber transformed into Ⅱ fiber in rabbit

目的通过在体外对家兔骨骼肌两型肌纤维细胞进行不同培养方法的摸索和对其标志蛋白MHC同功型变化的检测,探索两型肌纤维细胞间的转化条件。方法运用改良的肌球蛋白ATP酶组织化学染色法对家兔骨骼肌的肌纤维类型进行染色并观察;应用RT-PCR方法检测在不同培养条件下家兔骨骼肌MHC亚型mRNA的表达情况。结果肌组织消化组:固有半膜肌表达MHCⅠ型及少量的MHCⅡ型,副半膜肌表达MHCⅡa和Ⅱb型。细胞培养组:常氧高糖组固有半膜肌表达MHCⅡa和Ⅱb,不表达MHCⅠ型;副半膜肌表达MHCⅡa和Ⅱb,不表达MHCⅠ型;低氧高糖组固有半膜肌表达MHCⅡa和Ⅱb,不表达MHCⅠ型;副半膜肌表达MHCⅡb,不表达MHCⅠ型。结论含15%FBS的常氧高糖培养基适宜骨骼肌细胞生长,并且在低氧高糖条件下,骨骼肌Ⅰ型纤维有向Ⅱ型纤维转化的趋势。

Objective To explore suitable culture condition for typeⅠand typeⅡmuscle fiber cells by rabbit,the change of marker protein MHC isoforms of skeletal muscle fiber type was detected,and the transformation conditions between the two types of muscle fiber cells were preliminarily explored.Methods The modified myosin ATP enzyme histochemical staining method was used to stain and observe the muscle fiber types of inherent semimembranosus and sub-semimembranosus muscles in rabbits,and the expression of the MHC isoforms mRNA of the inherent semimembranosus and sub-semimembranosus muscles under different culture conditions was detected by RT-PCR.Results Non-cultured inherent semimembranosus cells expressed MHCⅠand a small amount of MHCⅡ,non-cultured sub-semimembranosus cells expressed MHCⅡa and MHCⅡb.Inherent semimembranosus cell with high glucose culture group expressed MHCⅡa and MHCⅡb,not MHCⅠ,and sub-semimembranosus expressed MHCⅡa and MHCⅡb,not MHCⅠ.Under condition of hypoxia and high glucose,inherent semimembranosus expressed MHCⅡa and MHCⅡb,not MHCⅠ,sub-semimembranosus expressed MHCⅡb,not MHCⅠ.Conclusion The normoxia and high glucose DMEM containing 15%fetal calf serum is suitable for the growth of skeletal muscle cells,which can promote the transformation of typeⅠfiber of skeletal muscle into typeⅡfiber in the condition of hypoxia and high glucose.