二花脸猪和大白猪睾丸生长激素受体基因表达的发育性变化

随机选取0、3、20、30、90、120和180日龄二花脸公猪和大白公猪各4头，用相对定量RT-PER法研究睾丸组织中生长激素受体（GHR）基因表达的发育性变化。结果表明，二花脸猪与大白猪睾丸GHR mRNA表达的发育模式不同，二花脸猪GHR mRNA相对表达量从0到30日龄逐渐上升，在90和120日龄呈阶段性降低（P〈0．05），之后在180日龄又再次上调；大白猪GHR mRNA相对表达量在出生当日最高，3日龄显著下降（P〈0．05），随后直至180日龄维持在较低水平并相对恒定。总的来说，二花脸猪睾丸GHR mRNA相对表达量显著高于大白猪（P〈0．05）。提示：不同品种猪睾丸GHR mRNA表达具有特定的发育模式，并可能与性成熟的早晚有关。

Developmental changes of growth hormone receptor gene expression in testicular tissue of Erhualian and Large White pigs

Samples of testicular tissue were collected from Erhualian and Large White boars at 0,3,20,30,90,120 and 180 days of age,respectively,for investigating the developmental patterns of growth hormone receptor(GHR)mRNA expression in testis of two breeds of pigs with relative quantitative RT-PCR using 18S rRNA as an internal standard.The results showed that the testicular GHR mRNA expression in Erhualian and Large White boars followed distinct patterns.The expression of testicular GHR mRNA in Erhualian boars increased from day 0 reaching the first peak on day 30.A temporal down-regulation was observed thereafter from day 90 to 120(P<0.05)before rising to the second peak on day 180.In contrast,the expression of testicular GHR mRNA in Large White boars was high at birth,and declined sharply(P<0.05)on day 3 to a significantly lower level that was stabilized throughout the period of investigation.In general,the expression of testicular GHR mRNA was higher in Erhualian boars than that in Large White boars(P<0.05).The results suggest that the porcine testicular GHR mRNA is expressed according to breed-specific developmental patterns,which may contribute to different timings of sexual maturation in different breeds of pigs.