Levels of insulin-like growth factor (IGF) binding proteins, luteinizing hormone and IGF-I receptors, and steroids in dominant follicles during the first follicular wave in cattle exhibiting regular estrous cycles.
Levels of insulin-like growth factor (IGF) binding proteins, luteinizing hormone and IGF-I receptors, and steroids in dominant follicles during the first follicular wave in cattle exhibiting regular estrous cycles.
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表现出规则动情周期的牛在第一个卵泡波期间优势卵泡中胰岛素样生长因子 (IGF) 结合蛋白、黄体生成素和 IGF-I 受体以及类固醇的水平。
DOI：
10.1210/endo.137.7.8770905
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发表时间：
1996
期刊：
影响因子：
4.8
通讯作者：
Echternkamp
中科院分区：
文献类型：
--
作者：
R.;E.;Stewart;L.;J.;Spicer;T.;D.;Hamilton;B.;Keefer;Dawson;L. G.;Morgan;E. S.;Echternkamp
Objectives of this study were to determine if concentrations of steroids, insulin-like growth factor -I (IGF-I), and IGF binding proteins (IGFBP) in follicular fluid and numbers of LH and IGF-I receptors change during growth of the dominant follicle. Ovarian follicular development was monitored daily via ultrasound in lactating Holstein cows. Animals underwent bilateral ovariectomy when the dominant follicle was first identified (days 4-6; estrus = day 0; early; n = 5) or when it stopped growing (days 8-12; late; n = 8). All follicles were classified as dominant (DF), large (LG; > = 6 mm in diameter, excluding DF) or small (SM; < 6 mm), follicular fluid was aspirated, and theca and granulosa cells were collected. Levels of IGFBP-2, assessed via ligand blotting, were greater (P < 0.05) in LG and SM follicles compared with DF in early cows. Levels of IGFBP-3 in follicular fluid were unaffected by follicle class. Numbers of specific 125I-hCG/LH binding sites in thecal cells were greater (P < 0.01) in DF compared with LG and SM follicles of both early and late cows. Numbers of specific 125I-hCG/LH binding sites in granulosa cells were similar for follicle sizes in early cows, but, in late cows, were greater (P < 0.01) in DF compared with SM follicles and were severalfold greater (P < 0.01) in late DF compared with early DF. Numbers of receptors for IGF-I in thecal cells were 2-fold greater (P < 0.05) in DP and LG compared with SM in late cows. Numbers of IGF-I receptors in granulosa cells were unaffected by size or growth of follicles, but were severalfold greater than in theca cells. Concentrations of estradiol were severalfold greater (P < 0.01) in DF compared with LG and SM in both early and late cows. Concentrations of androstenedione in early cows were greater (P < 0.05) in DF and SM compared with LG follicles. Concentrations of progesterone and IGF-I did not differ (P > 0.10) among follicle classes, but both were greater (P < 0.10) in late LG compared with early LG follicles. Concentrations of IGF-II in follicular fluid did not differ (P > 0.10) between early and late cows but were greater (P < 0.10) in SM than DF or LG follicles. We conclude that low amounts of IGFBP-2 and increased thecal binding sites for hCG/LH appear to be related to establishment of the dominant follicle during the first follicular wave in cattle exhibiting regular estrous cycles during late lactation.
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影响因子：
4.8
作者：
S. Chun;H. Billig;J. Tilly;I. Furuta;A. Tsafriri;A. Hsueh
通讯作者：
S. Chun;H. Billig;J. Tilly;I. Furuta;A. Tsafriri;A. Hsueh
影响因子：
5.8
作者：
ELROEIY, A;CHEN, XH;YEN, SSC
通讯作者：
YEN, SSC
影响因子：
3.6
作者：
FORTUNE, JE
通讯作者：
FORTUNE, JE
卵巢卵泡液中的胰岛素样生长因子结合蛋白可阻止卵巢颗粒细胞产生促卵泡激素刺激的类固醇。
影响因子：
4.8
作者：
Ui,M;Shimonaka,M;Shimasaki,S;Ling,N
通讯作者：
Ling,N
培养中的猪卵巢颗粒细胞对胰岛素样生长因子 (IGF) 结合蛋白 3 的蛋白水解降解：IGF-I 的调节。
影响因子：
4.8
作者：
Grimes,RW;Hammond,JM
通讯作者：
Hammond,JM