皖西白鹅与朗德鹅下丘脑-垂体-肌肉生长轴基因表达的比较

Somatropic axis gene expression in hypothalamus-pituitary-muscle of Wanxi white geese and Landaise Geese

选择90日龄的皖西白鹅和朗德鹅各20只,取下丘脑、垂体、胸肌组织。采用半定量逆转录多聚酶链式反应(RT-PCR)的方法,以-βactin为内标,对下丘脑中的生长激素释放激素(GHRH)、垂体中的生长激素(GH)、肌肉组织中生长激素受体(GHR)、胰岛素样生长因子-1(IGF-1)、胰岛素样生长因子-Ⅰ型受体(IGF-1R)的mRNA表达量分别进行比较分析,并分别与鹅的胸肌重及胸肌率进行相关性分析。结果表明:皖西白鹅的屠体质量胸肌重与朗德鹅无显著差异;皖西白鹅垂体中GH的mRNA表达低于朗德鹅(P<0.05),而下丘脑中GHRH和肌肉中GHR、IGF-1I、GF-1R mRNA在两品种间无显著差异;胸肌重与IGF-1 mRNA的表达显著正相关(r=0.57,P<0.01),而与GHRI、GF-1R mRNA无显著的相关性。结果提示,鹅肌肉的生长主要取决于GH的靶机制,而与GH无关。

Hypothalamus,pituitary and muscle tissue were sampled from Wanxi white geese and Landaise geese at 90 days of age,20 of each. The total RNA was extracted from Hypothalamus,Pituitary and Muscle to measure the abundance of the growth hormone releasing hormone （GHRH）,growth hormone （GH）,growth hormone receptor （GHR） ,insu.lin like gj＇owth factor-1 （IGF-1）and insulin like growth factor-I receptor（IGF-1R）by Semi-quantitative RT-PCR using β-aclin as an internal standard. Results showed that there were no significant difference between Wanxi white geese and Landaise geese in the dressed weight and pectoral muscle weight. GH mRNA expression was lower in Wanxi White geese than that in Landaise geese （P〈0.05）,but the mRNA expression of GHRH,GHR, IGF-1 ,and IGF-1R were no significant difference between two breeds. Significant positive correlation was found be-tween pectoral muscle weight and IGF-1 mRNA expression（r=0.57, P〈0.01）. The results suggest that the pectoral muscle growth of geese may be mainly depended on target mechanism of GH rather than GH itself.