Christenson L K, Stouffer R L
Division of Reproductive Sciences, Oregon Regional Primate Research Center, Beaverton 97006, USA.
J Clin Endocrinol Metab. 1997 Jul;82(7):2135-42. doi: 10.1210/jcem.82.7.4169.
Granulosa cells in the ovulatory follicle express messenger ribonucleic acid encoding vascular endothelial growth factor (VEGF), an agent that may mediate the neovascularization of the developing corpus luteum, but it is not known whether luteinizing granulosa cells synthesize and secrete VEGF during the periovulatory interval. Studies were designed to evaluate the effects of an in vivo gonadotropin surge on VEGF production by macaque granulosa cells (study 1) and to test the hypothesis that gonadotropins act directly on granulosa cells to regulate VEGF production (study 2). Monkeys received a regimen of exogenous gonadotropins to promote the development of multiple preovulatory follicles. Nonluteinized granulosa cells (i.e. preovulatory; NLGC) and luteinized granulosa cells (i.e. periovulatory; LGC) were aspirated from follicles before and 27 h after an ovulatory gonadotropin bolus, respectively. Cells were either incubated for 24 h in medium with or without 100 ng/mL hCG (study 1) or cultured for 6 days in medium with or without 100 ng/mL hCG or 0.1, 1, 10, and 100 ng/mL of recombinant human LH (r-hLH) or r-hFSH (study 2). Culture medium was assayed for VEGF and progesterone. In study 1, LGC produced 8-fold greater levels of VEGF than NLGC (899 +/- 471 vs. 111 +/- 26 pg/mL, mean +/- SEM; P < 0.05). In vitro treatment with hCG increased (P < 0.05) VEGF production by NLGC to levels that were not different from the LGC incubated under control conditions. In vivo bolus doses of r-hCG (100 and 1000 IU) and r-hFSH (2500 IU) were equally effective in elevating granulosa cell VEGF production. In study 2, in vitro treatment with r-hFSH, r-hLH, and hCG markedly increased (P < 0.05) VEGF and progesterone production by the NLGC in a dose- and time-dependent manner. By comparison, the three gonadotropins (100 ng/mL dose) only modestly increased VEGF and progesterone production by LGC. These experiments demonstrate a novel role for the midcycle surge of gonadotropin (LH/CG or FSH) in primates to promote VEGF production by granulosa cells in the periovulatory follicle. Further, the data demonstrate that FSH-like as well as LH-like gonadotropins directly stimulate VEGF synthesis by granulosa cells.
排卵卵泡中的颗粒细胞表达编码血管内皮生长因子（VEGF）的信使核糖核酸，VEGF可能介导发育中的黄体的新血管形成，但目前尚不清楚黄素化颗粒细胞在排卵前后的间隔期是否合成并分泌VEGF。本研究旨在评估体内促性腺激素激增对猕猴颗粒细胞VEGF产生的影响（研究1），并检验促性腺激素直接作用于颗粒细胞以调节VEGF产生的假设（研究2）。猴子接受外源性促性腺激素方案以促进多个排卵前卵泡的发育。分别在排卵性促性腺激素推注前和推注后27小时从卵泡中吸出未黄素化的颗粒细胞（即排卵前；NLGC）和黄素化的颗粒细胞（即排卵前后；LGC）。细胞在含有或不含有100 ng/mL hCG的培养基中孵育24小时（研究1），或在含有或不含有100 ng/mL hCG或0.1、1、10和100 ng/mL重组人LH（r-hLH）或r-hFSH的培养基中培养6天（研究2）。测定培养基中的VEGF和孕酮。在研究1中，LGC产生的VEGF水平比NLGC高8倍（899±471对111±26 pg/mL，平均值±标准误；P<0.05）。用hCG进行体外处理可使NLGC的VEGF产生增加（P<0.05），达到与在对照条件下孵育 的LGC无差异的水平。体内推注剂量的r-hCG（100和1000 IU）和r-hFSH（2500 IU）在提高颗粒细胞VEGF产生方面同样有效。在研究2中，用r-hFSH、r-hLH和hCG进行体外处理可使NLGC的VEGF和孕酮产生以剂量和时间依赖性方式显著增加（P<0.05）。相比之下，三种促性腺激素（100 ng/mL剂量）仅适度增加LGC的VEGF和孕酮产生。这些实验证明了促性腺激素（LH/CG或FSH）在灵长类动物中期激增在促进排卵前后卵泡颗粒细胞产生VEGF方面的新作用。此外，数据表明类似FSH以及类似LH的促性腺激素直接刺激颗粒细胞合成VEGF。
