重组生长激素促短肠大鼠结肠代偿机制的探讨

The mechanism of rGH in the promotion of colonic adaptation in short bowel rats

目的 探讨重组生长激素促短肠大鼠结肠代偿的作用机制。方法 将短肠大鼠分成肠内营养 (EN)和肠内营养 +重组生长激素 (EG)两组。结果 自术后第 15天起 ,EG组体重的减轻明显低于EN组 (P <0 0 5 ) ,术后第 2 1天起体重已大于术前 ;EG组氮平衡的改善明显好于EN组 ;血浆蛋白水平也高于EN组 (P <0 0 5 ) ;EG组结肠壁胰岛素样生长因子 1(IGF 1)mRNA含量比EN组明显升高〔(12 91± 43)vs .(10 2 6± 42 ) ,P <0 0 5〕 ,IGF 1受体mRNA含量明显降低〔(899± 5 )vs.(1113± 7) ,P <0 0 5〕 ;EG组的血IGF 1水平明显高于EN组〔(4 5 5± 10 7)ng/mlvs.(32 9± 6 8)ng/ml,P <0 0 5〕 ,GH水平也显著升高〔(9 7± 3 3)ng/mlvs .(5 8± 2 4)ng/ml,P <0 0 5〕。结论 重组生长激素可促使短肠大鼠IGF 1和结肠壁IGF 1mRNA的合成及残留肠道对营养物质吸收。

Objective To study the mechanism of rGH in the promotion of colonic morphologic adaption in short bowel rats.Method Twenty rats undergoing 80～85% small bowel resection were randomized into two groups receiving enteral nutrition (EN), and enteral nutrition plus GH (EG). Ten normal rats served as control (CONT). Result On post-op day 15, body weight in EG group was heavier than in EN group (P<005). The net nitrogen gain in EN group was less than that in CONT (P<005) and in EG group (P<001).The serum protein level of EG group was higher than EN group(P<005) The level of colonic muscoal IGF-1 mRNA was higher in EG than in EN (1*!291±43 vs. 1*!026±42,P<005), whereas the level of colonic muscoal IGF-1 receptor mRNA was lower than normal (899±5 vs. 1*!113±7,P<005). The levels of serum insulin-like growth factor-1 (IGF-1) of EG group was higher than EN(455±107*!ng/ml vs. 329±68*!ng/ml,P<005) The level of serum GH of EG group was higher than EN(97±33*!ng/ml vs. 58±24*!ng/ml,P<005) Conclusions rGH promotes the synthesise of serum IGF-1 and colonic muscoal IGF-1 mRNA, hence significantly elevates the colonic functional adaption to absorb nutrients.