人工光照对初情期前母兔生殖系统发育的影响  

Influence of Artificial Light on the Development of the Reproductive System in Prepubertal Female Rabbits(Oryctolagus cuniculus)

作　　者：苏行 任旭芳 梁小虎 胡馨悦 罗刚 王珺琦 李彦宏 刘哲良 王杰 胡深强 赖松家 SU Hang;REN Xu-Fang;LIANG Xiao-Hu;HU Xin-Yue;LUO Gang;WANG Jun-Qi;LI Yan-Hong;LIU Zhe-Liang;WANG Jie;HU Shen-Qiang;LAI Song-Jia(Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province,Sichuan Agricultural University,Chengdu 611130,China)

机构地区：[1]四川农业大学畜禽遗传资源发掘与创新利用四川省重点实验室

出　　处：《农业生物技术学报》2020年第2期251-259,共9页Journal of Agricultural Biotechnology

基　　金：现代农业产业技术体系建设专项(CARS-43-A-2);国家级大学生创新创业训练计划项目(1921996011);四川农业大学学科建设双支计划项目(03573037)

摘　　要：光照是影响母兔(Oryctolagus cuniculus)繁殖性能的关键环境因素之一,为揭示人工光照对初情期前母兔生殖系统发育的影响及其潜在作用机制,本研究选取48日龄天府黑兔母兔,随机等分成光照组和对照组,采用人工光照对光照组母兔进行处理,对照组则采用自然光照;处理结束后,进行屠宰并记录生殖器官指数,采用ELISA法检测血浆褪黑素(melatonin, MLT)、雌二醇(estradiol, E2)、前列腺素E2(prostaglandin E2, PGE2)和孕酮(progesterone, P4)含量,苏木精-伊红(hematoxylin&eosin, HE)染色观察卵巢、输卵管和子宫的组织学变化,qRT-PCR法检测MLT受体1A (MLT receptor 1A, MTNR1A)基因、P4受体(P4receptor, PR)基因、E2受体(E2receptorαandβ, ERA and ERB)基因及PGE2受体(PGE2receptor 1~4, EP1~4)基因在生殖系统中的相对表达量。结果显示,与对照组相比,人工光照显著增加了初情期前母兔双侧卵巢重、双侧输卵管重和双侧子宫重(P<0.05),并显著提高了双侧输卵管与双侧子宫指数(P<0.05)。组织学水平研究表明,人工光照处理后的卵巢上出现了三级卵泡和成熟卵泡,而在对照组仅存在原始卵泡、初级卵泡和次级卵泡;人工光照还增加了输卵管与子宫内膜、肌层和浆膜厚度。另外,人工光照导致血浆MLT水平下降、PGE2和P4水平升高,却显著降低了血浆E2水平(P<0.05)。此外,人工光照不仅显著或极显著增加了卵巢中MTNR1A、PR、ERB和EP1~3的表达量(P<0.05或P<0.01),也显著或极显著增加了输卵管中PR和EP2~4的表达量(P<0.05或P<0.01),同时还显著或极显著增加了子宫体中MTNR1A、PR、ERB和EP3以及子宫角中PR、EP1、EP3和EP4的表达量(P<0.05或P<0.01)。以上结果表明,人工光照可能通过间接调控下丘脑-垂体轴和直接作用于生殖系统两种方式影响血浆激素水平,随后激活各自受体介导的信号转导通路,协同促进初情期前母兔卵巢、输卵管和子宫的发育成熟。本研究为母Light is one of the crucial environmental factors affecting the reproductive performance of female rabbits(Oryctolagus cuniculus). This study aimed to reveal the influence of artificial light on the reproductive system development of prepubertal female rabbits as well as the underlying mechanisms. A total of sixty 48-day-old female Tianfu black rabbits were equally divided into the light and control groups. After 10 d of acclimation, the light group was treated with artificial light for consecutive 12 d(16 h per day), while the control group was fed under natural light. After treatment, 6 rabbits randomly selected from each group were slaughtered. Thereafter, the relative weight of reproductive organs was recorded, the concentrations of plasma melatonin(MLT), estradiol(E2), prostaglandin E2(PGE2), and progesterone(P4) were measured using ELISA,histological changes in the ovary, oviduct, and uterus were observed using hematoxylin & eosin(HE) staining,and qRT-PCR was used to detect the relative expression of the MLT receptor(MTNR1 A) gene, the P4 receptor(PR) gene, the E2 receptor(ERA and ERB) genes, and the PGE2 receptor(EP1~4) genes in the reproductive system. The results showed that compared to the control group, artificial light significantly increased the weight of bilateral ovaries, oviducts, and uteruses as well as the relative weight of bilateral oviducts and uteruses(P<0.05). Histological results showed that both tertiary and mature follicles were present in the ovaries treated with artificial light but were absent in the control group. Meantime, artificial light increased the thickness of the endometrium, the muscular layer, and the serosa of either the oviduct or uterus. In addition,compared to the control group, artificial light decreased plasma levels of MLT, increased those of PGE2 and P4,and significantly decreased those of E2(P<0.05). Finally, the mRNA levels of MTNR1 A and ERB in both the ovary and uterine body, PR in all reproductive organs, EP1~3 in the ovary, EP1 and EP3~4 in the uterine horn,an

关 键 词：母兔 人工光照 初情期启动 生殖系统 生殖激素 

分 类 号：S829.1[农业科学—畜牧学]