【摘要】 目的 :检测大鼠心脏容量超负荷 (volumeoverload ,VOL)时左心室内压变化诱导心肌原癌基因c -fos、c -jun、c -myc、egr- 1mRNA表达的时间变化规律。方法 :测定VOL、假手术对照组大鼠术后 30min、1、4、6、12及 48h左心室收缩压 (LVSP)和舒张末压 (LVEDP) ,用狭缝杂交检测 2组各时间左室心肌原癌基因表达 ,用密度仪进行定量分析。结果 :VOL大鼠术后LVSP显著低于假手术组 (P <0 0 5 ) ,48h最低 ;术后 30minLVEDP高于假手术组 (P <0 0 5 ) ,12h最高 ,48h与假手术组相近 (P >0 0 5 ) ;假手术组和阴性对照各原癌基因无阳性表达 ,AVF后 1h检测到c -fos、c -jun、egr- 1mRNA表达 ,4h检测到c -myc表达 ,均于 4h出现表达峰值 ,此后减弱 ,48hc -fos无表达 ,c -jun表达较弱 ,c -myc和egr- 1仍有较高表达。结论 :VOL大鼠LVEDP增加 ,首先诱导c -fos、c -jun、egr- 1表达 ,c -myc表达较晚 ,c -myc、c -jun、egr - 1表达持续时间较长 ,可能反映了活体VOL刺激心肌原癌基因表达时间变化规律 ;当室壁受到一定程度和一定时间的负荷牵拉后心肌原癌基因即开始表达 ,负荷的强弱可能并非重要因素更多还原

【Abstract】 AIM: To investigate the effect of intraventricular pressure change by volume overload (VOL) on expression of proto-oncogene c- fos ,c- jun ,c- myc and egr-1 . METHODS: Left ventricular systolic pressure(LVSP) and left ventricular end diastolic pressure (LVEDP) of rat with VOL induced by aortacaval fistula operation and rats of control group were measured at 30 min, 1, 4, 6, 12 and 48 h after the operation,these mRNAs at the foregoing time points were measured by slot bloting method and quantified with densitometry. RESULTS: Be compared with the control group, VOL rats LVSP decreased ( P <0.05) and declined most remarkably at 48 h,LVEDP elevated significantly at 30 min ( P <0.05), reached a maximal value at 12 h and the levels of control group at 48 h ( P >0.05) after the operation.The proto-oncogene expression signals were not detected in the control,negative controls and VOL rats at 30 min after the operation. The c- fos, c- jun and egr-1 mRNA signals appeared earlier,at 1 h, and c- myc mRNA increased later at 4 h.All reached peak value at 4 h and then declined gradually.The c- fos mRNA were not detected at 48 h. The c- myc ,c- 0jun and egr-1 mRNA persisted throught the entire observation period from 1 h to 48 h. CONCLUSIONS: During VOL early phase the overload have effect on expression of the proto-oncogene mRNA,c- fos, c- jun and egr-1 mRNA appear earlier, c- myc later, egr -1,c- jun and c- myc persist longer period, but the expressions do not strengthen with the ventricule wall load increase.This sequential induction pattern may reflect the time course regularity of the proto-oncogenes expression induced by VOL,and indicate the proto-oncogenes expression initiate while the heart load accumulate some extent and duration and the load magnitude may not play a critical role.更多还原