The ovarian expression of mRNAs for aromatase, IGF-I receptor, IGF-binding protein-2, -4 and -5, leptin and leptin receptor in cycling ewes after three days of leptin infusion.
The ovarian expression of mRNAs for aromatase, IGF-I receptor, IGF-binding protein-2, -4 and -5, leptin and leptin receptor in cycling ewes after three days of leptin infusion.
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瘦素输注三天后，循环母羊中芳香酶、IGF-I受体、IGF结合蛋白-2、-4和-5、瘦素和瘦素受体的mRNA的卵巢表达。
DOI：
10.1530/rep.1.00557
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发表时间：
2005
期刊：
影响因子：
3.8
通讯作者：
R. Scaramuzzi
中科院分区：
文献类型：
--
作者：
M. Muñoz;P. Findlay;C. Adam;G. Wax;B. Campbell;N. Kendall;M. Khalid;M. Forsberg;R. Scaramuzzi
本试验测定了10只绵羊在发情周期黄体期注射重组人瘦素(n=5；1微g/h)或生理盐水(n=5)72 h后，芳香酶、胰岛素样生长因子-I受体(IGF-IR)、胰岛素样生长因子结合蛋白(IGFBP)-2、-4和-5、瘦素和瘦素长型受体(Ob-Rb)的mRNAs的表达模式。输注结束时，用溶黄体剂量的前列腺素F2a类似物诱导卵泡期，32h后收集卵巢。每只母羊的一个卵巢用低温恒温器在-20℃下以10微米连续切开，所有卵泡直径1 mm，计数并用芳香酶、IGF-IR和IGFBP-2、-4和-5的特异性寡核苷酸探针以及瘦素和Ob-Rb的特异性核糖体探针进行探测。瘦素基因在卵泡膜细胞和颗粒细胞中表达，Ob-Rb基因在部分有腔卵泡的颗粒细胞中表达。瘦素使直径<gt；/=3.5 mm(1.0+/-0.36(S.E.M.))的卵泡数增加一倍Vs2.4+/-0.24；对照组vs瘦素；P<；0.02)，但对1<；3.5 mm卵泡数无影响。瘦素对表达芳香化酶mRNA的卵泡数无影响，但显著减少表达IGF-IR(10.7+/-0.79 vs 7.4+/-0.81；对照组vs瘦素；P<；0.05)、IGFBP-2(10.0+/-0.82 vs 5.2+/-0.87；对照组vs瘦素；P<；0.05)和IGFBP-5(5.2+/-1.60 vs 1.2+/-0.30；对照组vs瘦素；P<；0.05)。Leptin使IGFBP-2mRNA阳性卵泡直径增加(1.50±0.15vs2.2+/-0.31 mm；对照组vsLeptin；P<；0.05)，并增加IGFBP-2mRNA表达(0.30+/-0.021 vs0.39+/-0.027个任意单位；对照组vsLeptin；P<0.05)和IGFBP-5(0.46+/-0.019 vs0.25+/-0.053个任意单位；对照组vsLeptin；P<；0.05)。对照组只有两个卵泡膜上有IGFBP-4的表达。Leptin使表达Ob-Rb mRNA的卵泡数增加(0.25+/-0.25vs1.40+/-1.17；对照组vs Leptin；P<；0.05)，但对表达Leptin mRNA的卵泡数无影响。瘦素降低血浆雌二醇浓度(P<；0.001)，升高促卵泡激素浓度(P<；0.001)和胰岛素浓度(P<；0.001)，但对血糖浓度无影响。这些数据表明：(1)绵羊颗粒细胞表达Ob-Rb和Leptin的mRNA；(2)Leptin使卵泡数增加。此外，这些数据表明，瘦素抑制雌二醇的产生不是通过抑制芳香酶基因的表达来实现的。这些结果表明，瘦素在卵泡中的作用是通过IGF系统介导的，因为瘦素上调了IGFBP-2和-5mRNA的表达。瘦素还减少了表达IGF-IR和IGFBP-2和-5的卵泡数量。我们认为，瘦素对IGF系统的这些作用降低了IGF-I的生物利用度，导致雌二醇产生减少。
An experiment was carried out to determine the pattern of follicular expression of mRNAs for aromatase, IGF-I receptor (IGF-IR), IGF-binding protein (IGFBP)-2, -4 and -5, leptin and the long form of the leptin receptor (Ob-Rb) in ten ewes infused with human recombinant leptin (n = 5; 1 microg/h) or saline (n = 5) for 72 h in the luteal phase of the oestrous cycle. At the end of infusion a follicular phase was induced with a luteolytic dose of a prostaglandin F2alpha analogue and the ovaries were collected 32 h later. One ovary from each ewe was serially sectioned at 10 microm using a cryostat at -20 degrees C. All follicles >1 mm in diameter were counted and probed with specific oligoprobes for aromatase, IGF-IR and IGFBP-2, -4 and -5 and specific riboprobes for leptin and Ob-Rb. Leptin mRNA was detected in theca and granulosa cells and Ob-Rb mRNA was detected only in granulosa cells, of some, but not all antral follicles. Leptin doubled the number of follicles with a diameter >/=3.5 mm (1.0 +/- 0.36 (s.e.m.) vs 2.4 +/- 0.24; control vs leptin; P < 0.02) but had no effect on the number of >/=1 < 3.5 mm follicles. Leptin had no effect on the number of follicles expressing aromatase mRNA but it decreased significantly the number of follicles expressing mRNA for IGF-IR (10.7 +/- 0.79 vs 7.4 +/- 0.81; control vs leptin; P < 0.05), IGFBP-2 (10.0 +/- 0.82 vs 5.2 +/- 0.87; control vs leptin; P < 0.05) and IGFBP-5 (5.2 +/- 1.60 vs 1.2 +/- 0.30; control vs leptin; P < 0.05). Leptin increased the diameter of IGFBP-2 mRNA-positive follicles (1.5 +/- 0.15 vs 2.2 +/- 0.31 mm; control vs leptin; P < 0.05) and increased follicular mRNA expression for IGFBP-2 (0.30 +/- 0.021 vs 0.39 +/- 0.027 arbitrary units; control vs leptin; P < 0.05) and IGFBP-5 (0.46 +/- 0.019 vs 0.25 +/- 0.053 arbitary units; control vs leptin; P < 0.05). The mRNA for IGFBP-4 was detected in the theca of only two follicles from the control group. Leptin increased the number of follicles expressing Ob-Rb mRNA (0.25 +/- 0.25 vs 1.40 +/- 1.17; control vs leptin; P < 0.05) but had no effect on the number expressing leptin mRNA. Leptin decreased plasma concentrations of oestradiol (P < 0.05) and increased concentrations of FSH (P < 0.001) and insulin (P < 0.001), with no effect on glucose concentrations. These data show that: (i) ovine granulosa cells express mRNA for Ob-Rb and leptin and (ii) leptin increased the number of follicles >/=3.5 mm. Furthermore, the data suggest that suppression of oestradiol production by leptin is not mediated by inhibition of aromatase gene expression. Finally, the data indicate that the action of leptin in ovarian follicles is mediated by the IGF system, because leptin increased mRNA expression of IGFBP-2 and -5. Leptin also decreased the number of follicles expressing IGF-IR and IGFBP-2 and -5. We suggest that these actions of leptin on the IGF system decrease the bioavailability of IGF-I, resulting in decreased oestradiol production.
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影响因子：
4.8
作者：
R. Zachow;D. Magoffin
通讯作者：
R. Zachow;D. Magoffin
影响因子：
2.2
作者：
Ghizzoni, L;Barreca, A;Bernasconi, S
通讯作者：
Bernasconi, S
在用玉米赤霉醇处理的生长中，身体成分、瘦素和瘦素受体及其与生长激素 (GH) 轴的关系。
影响因子：
2.1
作者：
Narro,LA;Thomas,MG;Silver,GA;Rozeboom,KJ;Keisler,DH
通讯作者：
Keisler,DH
影响因子：
3.6
作者：
R. Zachow;S. Weitsman;D. Magoffin
通讯作者：
R. Zachow;S. Weitsman;D. Magoffin
内皮细胞表达胰岛素样生长因子结合蛋白 2 至 6。
DOI：
10.1210/mend.6.11.1282670
发表时间：
1992
期刊：
Molecular endocrinology (Baltimore, Md.)
影响因子：
--
作者：
Moser,DR;LoweJr,WL;Dake,BL;Booth,BA;Boes,M;Clemmons,DR;Bar,RS
通讯作者：
Bar,RS