Aim: To assess whether exogenous estradiol has any effect on migration of primordial germ cells (PGCs) in the chick. Methods: Fertilized eggs were treated with 17beta-estradiol (E2) (80 lag/egg) at stage X (d...Aim: To assess whether exogenous estradiol has any effect on migration of primordial germ cells (PGCs) in the chick. Methods: Fertilized eggs were treated with 17beta-estradiol (E2) (80 lag/egg) at stage X (day 0 of incubation), stages 8-10 (incubation 30 h) and 13-15 (incubation 55 h). Controls received vehicle (emulsion) only. Changes in PGC number were measured on different days according to developmental stages. Results: In male right gonads, but not in female left gonads, at stages 28-30 (incubation 132 h) significant decreases in the mean number of PGCs aggregating were observed compared with the controls (P 〈 0.05) while the total PGC number in the right and left gonads at each stage did not change (P 〉 0.05). Conclusion: The present study provides evidence that E2 has significant effects on the localization of PGCs in male right, but not female left, gonads of chicken embryos at stages 28-30, compared with controls. (Asian J Andro12008 Mar; 10: 243-248)展开更多
To study the effects of 17beta-estradiol (E2 ) and progesterone (P4) levels on superovulatory response and recipients conception rate, the E2 and P4 levels of embryo donor (Borderdale) and recipient ewes (Inner...To study the effects of 17beta-estradiol (E2 ) and progesterone (P4) levels on superovulatory response and recipients conception rate, the E2 and P4 levels of embryo donor (Borderdale) and recipient ewes (Inner Mongolian sheep) were determined during multiple ovulation and em- bryo transfer (MOET). The results showed that the E2 level increased from the day of initiation by CIDR (Controlled internal drug release devices) treatment and decreased to 3.18± 1.32 pg/ml on the day of superovulatory estrus. On the day of embryo collection, the ewes having higher levels of estrogenic peak showed better superovulatory response than the other groups having comparatively lower levels. On the day of initiation of super- ovulatory treatment, the ewes having lower levels of P4 showed better superovulatory response than those having higher levels of P4. The E2 level of the early abortion group increased from Day 0 to Day 45, while that of two pregnant recipient groups came down from Day 0 to Day 30. The ser- um P4 level of the early abortion group was significantly lower than that of the pregnant recipient groups on Day 45 ( P 〈 0.05), but no significant difference was found between the two pregnant groups after Day 30. Therefore, the levels of E2 and P, on definite time affect superovulatory re- sponse of donors and conception rate of recipients during MOET.展开更多
Aim: To investigate whether estrogen stimulates the proliferation of spermatogonia or induces spermatogenesis in cryptorchid mice. Methods: Mice were surgically rendered cryptorchid, then treated with different dose...Aim: To investigate whether estrogen stimulates the proliferation of spermatogonia or induces spermatogenesis in cryptorchid mice. Methods: Mice were surgically rendered cryptorchid, then treated with different doses of 17β- estradiol (E2) s.c. once a day. Mice were killed at sexual maturity (45 days of age), and histological analysis and inununofluorescence were performed. Serum follicle stimulating hormone (FSH), estradiol, testosterone and luteinizing hormone (LH) were measured. Results: Low doses of E2 had no notable effect on spermatogonia, but at higher doses, E2 stimulated the proliferation of spermatogonia. Conclusion: E2 has a dose-related mitogenic effect on spermatogonia.展开更多
基金Acknowledgment This work was supported by the National Natural Science Foundation of China (No. 30270648 and No. 30500270), Zhejiang Province Scientific and Technological Project (No. 2005C22052) and Zhejiang Province Science Foundation (No. Y304194). We thank Dr Ji- Min Zhang of the University of California for linguistic revision of the manuscript.
文摘Aim: To assess whether exogenous estradiol has any effect on migration of primordial germ cells (PGCs) in the chick. Methods: Fertilized eggs were treated with 17beta-estradiol (E2) (80 lag/egg) at stage X (day 0 of incubation), stages 8-10 (incubation 30 h) and 13-15 (incubation 55 h). Controls received vehicle (emulsion) only. Changes in PGC number were measured on different days according to developmental stages. Results: In male right gonads, but not in female left gonads, at stages 28-30 (incubation 132 h) significant decreases in the mean number of PGCs aggregating were observed compared with the controls (P 〈 0.05) while the total PGC number in the right and left gonads at each stage did not change (P 〉 0.05). Conclusion: The present study provides evidence that E2 has significant effects on the localization of PGCs in male right, but not female left, gonads of chicken embryos at stages 28-30, compared with controls. (Asian J Andro12008 Mar; 10: 243-248)
基金funded by Agricultural Research Institute"948"Program of China(2000-2005)
文摘To study the effects of 17beta-estradiol (E2 ) and progesterone (P4) levels on superovulatory response and recipients conception rate, the E2 and P4 levels of embryo donor (Borderdale) and recipient ewes (Inner Mongolian sheep) were determined during multiple ovulation and em- bryo transfer (MOET). The results showed that the E2 level increased from the day of initiation by CIDR (Controlled internal drug release devices) treatment and decreased to 3.18± 1.32 pg/ml on the day of superovulatory estrus. On the day of embryo collection, the ewes having higher levels of estrogenic peak showed better superovulatory response than the other groups having comparatively lower levels. On the day of initiation of super- ovulatory treatment, the ewes having lower levels of P4 showed better superovulatory response than those having higher levels of P4. The E2 level of the early abortion group increased from Day 0 to Day 45, while that of two pregnant recipient groups came down from Day 0 to Day 30. The ser- um P4 level of the early abortion group was significantly lower than that of the pregnant recipient groups on Day 45 ( P 〈 0.05), but no significant difference was found between the two pregnant groups after Day 30. Therefore, the levels of E2 and P, on definite time affect superovulatory re- sponse of donors and conception rate of recipients during MOET.
基金Acknowledgment This work was supported by the National Natural Science Foundation of China (No. 30200195). We thank Dr Hai-Bin Wang for taking photographs and Dr Su-Hui Wu (Henan Normal University, China) for statistical analysis. We thank the faculty of Huanghuai University for supporting Dr En-Zhong Li.
文摘Aim: To investigate whether estrogen stimulates the proliferation of spermatogonia or induces spermatogenesis in cryptorchid mice. Methods: Mice were surgically rendered cryptorchid, then treated with different doses of 17β- estradiol (E2) s.c. once a day. Mice were killed at sexual maturity (45 days of age), and histological analysis and inununofluorescence were performed. Serum follicle stimulating hormone (FSH), estradiol, testosterone and luteinizing hormone (LH) were measured. Results: Low doses of E2 had no notable effect on spermatogonia, but at higher doses, E2 stimulated the proliferation of spermatogonia. Conclusion: E2 has a dose-related mitogenic effect on spermatogonia.