目的:探讨降钙素基因相关肽(calcitoningene.relatedpeptide,CGRP)对小鼠卵母细胞体外成熟的影响。方法:6周龄雌性昆明小鼠腹腔注射孕马血清促性腺激素(pregnantmareserumgonadotropin,PMSG)10U48h后处死,取出卵巢收集卵母细胞以30~40枚/孔的密度接种于培养板内,以不同浓度CGRV(0,10^-10,10^-9,10^-9mol/L)处理24h后检测生发泡破裂(germinalvesiclebreakdown,GVBD)率和第一极体(polarbodyI,PBI)排出率;收集、培养人卵巢颗粒细胞,以不同浓度CGRV(0,10^-10,10^-9,10^-8mol/L)处理24h后测定颗粒细胞内cAMP浓度。结果:外源性CGRP处理小鼠卵母细胞可浓度依赖性地降低GVBD率及PBI排出率;外源性CGRP处理人颗粒细胞,可浓度依赖性地增高细胞内cAMP浓度。结论:CGRP抑制小鼠卵母细胞成熟可能与其增加颗粒细胞内cAMP浓度有关。
Objective: To explore the effect of calcitonin gene-related peptide (CGRP) on murine oocyte maturation. Methods: After injection of pregnant mare serum gonadotropin (PMSG, 10 U, i.p.) for 48 h, 6-week old female Kunming mice were killed, and the cumulus oocyte complexes (COCs) were collected from ovaries and inoculated in the culture plate by 30-40/hole. The COCs were treated with 4 concentrations of CGRP (0, 10-10, 10-9, and 10-8mol/L), and the germinal vesicle breakdown (GVBD) and polar body I (PBI) were examined. Human granulosa cells were also cultured with CGRP (0, 10 10-9, 10-8 mol/L) and levels of intraceUular cyclic adenosine monophosphate (cAMP) were measured. Results: Exogenous CGRP caused a decrease in GVBD and PBI in COCs, and an increase in cAMP levels in human granulosa cells in a concentration-dependent manner.Conclusion: CGRP can inhibit the oocyte maturation, which may be related to the increased content of cAMP in granulosa cells.