绍兴、高邮2品种鸭下丘脑GnRH-Ⅰ mRNA与血清中NPY及E_2浓度变化的比较  

Developmental Changes of Hypothalamic GnRH-Ⅰ Gene Expression,Serum NPY and E_2 in Shaoxin and Gaoyou Laying Duck

作　　者：倪迎冬[1] 周玉传[1] 王亚菊[1] 卢立志[1] 赵茹茜[1] 

机构地区：[1]南京农业大学农业部动物生理生化重点开放实验室,江苏南京210095

出　　处：《中国兽医学报》2005年第6期624-627,共4页Chinese Journal of Veterinary Science

基　　金：国家自然科学基金农业倾斜项目(39770540)

摘　　要：分别于30、60、90、120和150日龄随机选取绍兴母鸭和高邮母鸭各15羽,宰杀后采样,采用相对定量RT-PCR及RIA法检测了下丘脑GnRH-Ⅰ mRNA和血清中NPY、E2水平的发育性变化,并进行了品种间比较.结果表明:30～120日龄期间,绍兴母鸭下丘脑GnRH-Ⅰ mRNA含量呈逐渐上升趋势,120日龄达峰值,且显著高于30和60日龄(P<0.05);150日龄稍有下降,但仍维持较高水平.整个试验期间,尽管高邮母鸭下丘脑GnRH-Ⅰ mRNA的基础表达水平较高,但未见明显的日龄间差异(P>0.05).RIA结果显示:30日龄绍兴母鸭血清中NPY浓度较高,60日龄显著降低(P<0.01),并维持在此低水平至120日龄,但在150日龄时极显著升高(P<0.01).高邮母鸭在30～90日龄期间,血清中NPY浓度呈逐渐下降趋势,与绍兴母鸭血清中NPY浓度的变化模式相似;120日龄时显著升高,但在150日龄时极显著下降(P<0.01),表现出与绍兴母鸭不同的变化模式.2品种鸭血清E2浓度变化趋势相同,30～120日龄处于低水平状态,150日龄显著增加,150日龄绍兴母鸭血清E2浓度极显著升高且极显著高于同日龄高邮母鸭(P<0.01).结果提示:(1)绍兴母鸭下丘脑GnRH-Ⅰ基因表达的上调可能是其性成熟启动早的关键因素;(2)NPY可能以性激素依赖性方式促进鸭性成熟的启动.An increase in pulsatile release of GnRH-Ⅰ is essential for the onset of sexual maturation,and there is evidence indicating that GnRH neurons themselves have endogenous pulse-generating mechanism,but that the pulsatility of GnRH release is also modulated by input from neuropeptide Y（NPY） and other neurons. In this study,we measured the hypothalamic GnRH-1 mRNA contents in Shaoxing and Gaoyou ducks by RT-PCR using 18S rRNA as an internal-standard,meanwhile we measured the serum NPY ＆ E2 concentrations by RIA from 30 to 150 day-old ducks. The results showed that the level of hypothalamic GnRH-Ⅰ mRNA elevated gradually during sexual maturation in Shaoxing ducks, 120-day-old ducks exhibited the highest level which was significantly higher than that of D30,D60 and D90,then on 150-day-old the hypothalamic GnRH-Ⅰ mRNA kept on the high level. However,there were no such developmental changes in Gaoyou ducks. RIA results showed that the patterns of serum concentration of NPY are similar in early development between the two breeds,which both went down till D90,later they showed significant difference. On D150 Shaoxing ducks serum NPY concentration elevated terribly which was higher than any other experimental days,however,at this point that of Gaoyou ducks declined significantly which appeared notably lower than that of corresponding period of Shaoxing ducks. At the same time,RIA showed that the variation mode of serum E2 concentration were similar between the two breeds,that serum E2 was very lower before D120,on D150 Shaoxing ducks serum E2 was very high which paralleled with the changes of serum NPY. These results suggested：（1）the upregulation of hypothalamic GnRH-Ⅰ gene expression is necessary for the onset of sexual maturation in birds. （2）NPY may stimulate the onset of sexual maturation and its function appears to be dependant on the sexual steroids.

关 键 词：促性腺激素释放激素-Ⅰ 神经肽Y 雌二醇 性成熟 绍兴母鸭 高邮母鸭 

分 类 号：S822[农业科学—畜牧学]