The FecB (Booroola) gene acts at the ovary:: in vivo evidence
The FecB (Booroola) gene acts at the ovary:: in vivo evidence
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DOI：
10.1530/rep.0.1260101
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发表时间：
2003-07-01
期刊：
影响因子：
3.8
通讯作者：
Webb, R
中科院分区：
文献类型：
--
作者：
Campbell, BK;Baird, DT;Webb, R
本研究的目的是通过测量卵巢对促性腺激素的标准化治疗的反应来区分Fec B基因的垂体和卵巢作用，所述促性腺激素用于模拟在母羊卵巢周期的卵泡期发生的FSH和LH的变化，具有（Fec（B/-），n = 6）和不具有（Fec（+/+），n = 9）基因，通过用强有力的GnRH拮抗剂预处理而使其促性腺激素功能减退。本研究通过收集卵巢静脉血和超声检查，对自体卵巢移植母羊的卵泡功能进行了评估。促性腺激素方案导致FSH和LH的浓度与正常周期中的浓度相似，并且在基因型之间没有差异。所有动物均出现卵泡发育和排卵，雌二醇、雄烯二酮和白藜芦醇A的分泌模式均正常。尽管有这些内分泌相似性，但FSH输注刺激的窦卵泡群体保留了特征性的基因型差异，Fec（+/+）动物的卵巢含有一系列卵泡大小，其中小卵泡比例降低，（直径< 3.5毫米）和中等（直径3.5-4.5 mm）卵泡以及大卵泡（直径大于或等于4.5 mm），而Fec（B/-）母羊的卵巢不含直径> 4.5 mm的卵泡。这种基因型差异在排卵后仍然存在，基因携带者排卵前卵泡/黄体（3.8 ± 0.3）比非基因携带者（1.7 ± 0.3; 11.4 ± 0.9 mm; P < 0.05）直径小（5.3 ± 0.3 mm）。尽管FSH和LH刺激的浓度和模式相同，但携带Fec（B）基因突变的母羊比非基因携带者能够排卵更多的卵泡，本研究的结果支持Fec（B）基因作用于卵巢以增强卵巢对促性腺激素刺激的敏感性的假设。
The aim of this study was to differentiate between pituitary and ovarian actions of the FecB gene by measuring the ovarian response to a standardized treatment with gonadotrophins designed to mimic the changes in FSH and LH that occur in the follicular phase of the ovarian cycle in ewes, with (Fec(B/-), n = 6) and without (Fec(+/+), n = 9) the gene, that were rendered hypogonadotrophic by pretreatment with a potent antagonist of GnRH. Ewes with ovarian autotransplants were used to facilitate the assessment of follicular function by the collection of ovarian venous blood and ultrasonography. The gonadotrophin regimen resulted in concentrations of FSH and LH that were similar to concentrations found in a normal cycle and did not differ between genotypes. Follicular development and ovulation occurred in all animals, and patterns of secretion of oestradiol, androstenedione and inhibin A were normal. Despite these endocrine similarities, the antral follicle population stimulated by FSH infusion retained the characteristic genotypic difference with the ovaries of Fec(+/+) animals containing a range of follicle sizes with decreasing proportions of small (< 3.5 mm in diameter) and medium (3.5-4.5 mm in diameter) follicles as well as large follicles (greater than or equal to 4.5 mm in diameter), whereas the ovaries of Fec(B/-) ewes contained no follicles of > 4.5 mm in diameter. This genotypic difference was retained after ovulation with gene carriers having more preovulatory follicles/corpora lutea (3.8 +/- 0.3) of a smaller diameter (5.3 +/- 0.3 mm) than did non-gene carriers (1.7 +/- 0.3; 11.4 +/- 0.9 mm; P < 0.05). As ewes carrying the Fec(B) gene mutation were able to ovulate more follicles than non-gene carriers, despite identical concentrations and patterns of FSH and LH stimulation, the results of this study support the hypothesis that the Fec(B) gene acts at the ovary to enhance ovarian sensitivity to gonadotrophic stimulation.