CAJ | 학술논문

通过给SD大鼠注射AMPK激动剂AICAR,提高大鼠骨骼肌中AMPK的活性,探讨AMPK活性变化对骨骼肌蛋白质降解的作用。采用同位素技术测定腓肠肌中AMPK活性的变化;采用实时荧光定量PCR技术,测定腓肠肌中MuRF1、MAFbx基因表达量的变化。结果显示AICAR注射后1、2、7 h,AMPK活性与对照组相比升高,差异有显著性或非常显著性意义（P〈0.05或P〈0.01）;AICAR注射后7 h,AMPK活性开始下降。AICAR注射后1、2 h,MAFbx mRNA、MuRF1 mRNA表达量与对照组相比升高,分别升高2.45、2.23倍和2.67、2.30倍,差异有非常显著性意义（P〈0.01）;AICAR注射后7 h,MuRF1 mRNA表达量升高了2.01倍,差异有显著性意义（P〈0.05）;而MAFbx mRNA表达有升高趋势,但差异没有显著性。3-MH质量摩尔浓度各组间差异没有显著性意义。结果说明：（1）大鼠一次性注射AICAR后,能显著提高骨骼肌中AMPK的活性,AMPK活性的升高能促进MAFbx mRNA和MuRF1 mRNA的表达,促进骨骼肌蛋白质的降解;（2）推测在反映骨骼肌蛋白质降解方面,MAFbx mRNA和MuRF1 mRNA比3-MH的敏感度要高。
통과급SD대서주사AMPK격동제AICAR,제고대서골격기중AMPK적활성,탐토AMPK활성변화대골격기단백질강해적작용。채용동위소기술측정비장기중AMPK활성적변화;채용실시형광정량PCR기술,측정비장기중MuRF1、MAFbx기인표체량적변화。결과현시AICAR주사후1、2、7 h,AMPK활성여대조조상비승고,차이유현저성혹비상현저성의의（P〈0.05혹P〈0.01）;AICAR주사후7 h,AMPK활성개시하강。AICAR주사후1、2 h,MAFbx mRNA、MuRF1 mRNA표체량여대조조상비승고,분별승고2.45、2.23배화2.67、2.30배,차이유비상현저성의의（P〈0.01）;AICAR주사후7 h,MuRF1 mRNA표체량승고료2.01배,차이유현저성의의（P〈0.05）;이MAFbx mRNA표체유승고추세,단차이몰유현저성。3-MH질량마이농도각조간차이몰유현저성의의。결과설명：（1）대서일차성주사AICAR후,능현저제고골격기중AMPK적활성,AMPK활성적승고능촉진MAFbx mRNA화MuRF1 mRNA적표체,촉진골격기단백질적강해;（2）추측재반영골격기단백질강해방면,MAFbx mRNA화MuRF1 mRNA비3-MH적민감도요고。
By injecting AICAR,an AMPK excitant,into SD rats to boost the activity of AMPK in the skeletal muscles of the rats,the authors probed into the effects of AMPK activity changes on the degradation of proteins in skeletal muscles.The authors measured the changes of the AMPK activity in gastrocnemius by using isotope technology,and measured the changes of the level of expression of genes MuRF1 and MAFbx in gastrocnemius by using real time fluorescence quantification PCR technology.Results： 1 h,2 h and 7 h after AICAR was injected,the AMPK activity increased as compared with the control group,and the differences were significant or very significant（P0.05 or P0.01）,and 7 h after AICAR was injected,the AMPK activity started to decrease;1 h and 2 h after AICAR was injected,the levels of expression of MAFbx mRNA and MuRF1 mRNA increased respectively by 2.45 times,2.23 times and 2.67 times,2.30 times as compared with the control group,and the differences were very significant（P0.01）;7 h after AICAR was injected,the level of expression of MuRF1 mRNA increased by 2.01 times,and the difference was significant（P0.05）,while the level of expression of MAFbx mRNA increased somewhat,but the difference was not significant;there was no significant difference in the 3-MH content between various groups.The results indicated the followings： 1） after AICAR was injected into the rats once,it can significantly increase the activity of AMPK in skeletal muscles,while the increase of the AMPK activity can boost the expression of MAFbx mRNA and MuRF1 mRNA and the degradation of proteins in skeletal muscles;2） the authors conjectured that in terms of reflecting the degradation of proteins in skeletal muscles,MAFbx mRNA and MuRF1 mRNA are more sensitive than 3-MH.