Ortega Serrano P V, Guzmán A, Hernández-Coronado C G, Castillo-Juárez H, Rosales-Torres A M
Universidad Autónoma Metropolitana-Xochimilco Estudiante de Posgrado en Ciencias Agropecuarias, Ciudad de México, México.
Laboratorio Bioquímica de la Reproducción, Departamento de Producción Agrícola y Animal, Universidad Autónoma Metropolitana-Xochimilco, Ciudad de México, México.
Reprod Domest Anim. 2016 Dec;51(6):985-991. doi: 10.1111/rda.12777. Epub 2016 Sep 21.
The vascular endothelial growth factor (VEGF) is essential for follicular development by promoting follicular angiogenesis, as well as for the proliferation and survival of granulosa cells. The biological effects of VEGF are regulated by two membrane receptors, VEGFR1 and VEGFR2, and two soluble receptors, sVEGFR1 and sVEGFR2, which play an antagonistic role. Thus, the objective of this study was to identify the mRNA expression pattern of total VEGF, VEGFR1, VEGFR2, sVEGFR1 and sVEGFR2 in bovine preselected follicles (PRF) and post-selected follicles (POF). The mRNA expression of these five genes in both granulosa cells (GC) and theca cells (TC) was compared between follicles classified as PRF and POF based on their diameter and on their ratio of estradiol/progesterone (E2/P4). Results showed a lower expression of mRNA of sVEGFR1 and sVEGFR2 in POF than in PRF (p < .05). Regarding the mRNA expression of total VEGF, VEGFR1 and VEGFR2, there was no difference between POF and PRF follicles (p > .05). Our results showed that the mRNA expression of VEGFR2 and sVEGFR1 was more abundant than the expression of VEGFR1 and sVEGFR2, while GC was the main source of mRNA for total VEGF. On the other hand, TC was the follicular compartment where the receptors were most expressed. Our results suggest that non-dominant follicles maintain a greater concentration of the mRNA expression of both membrane and soluble VEGF receptors. On the other hand, follicular dominance is related to a reduction in the mRNA expression of sVEGFR1 and sVEGFR2, which may favour VEGF binding with VEGFR2 and, hence, improve the follicular health and development.
血管内皮生长因子（VEGF）通过促进卵泡血管生成以及颗粒细胞的增殖和存活，对卵泡发育至关重要。VEGF的生物学效应由两种膜受体VEGFR1和VEGFR2以及两种可溶性受体sVEGFR1和sVEGFR2调节，它们发挥拮抗作用。因此，本研究的目的是确定牛预选卵泡（PRF）和选定后卵泡（POF）中总VEGF、VEGFR1、VEGFR2、sVEGFR1和sVEGFR2的mRNA表达模式。根据卵泡直径及其雌二醇/孕酮（E2/P4）比值，将卵泡分为PRF和POF，比较这五种基因在颗粒细胞（GC）和卵泡膜细胞（TC）中的mRNA表达。结果显示，POF中sVEGFR1和sVEGFR2的mRNA表达低于PRF（p < 0.05）。关于总VEGF、VEGFR1和VEGFR2的mRNA表达，POF和PRF卵泡之间没有差异（p > 0.05）。我们的结果表明，VEGFR2和sVEGFR1的mRNA表达比VEGFR1和sVEGFR2更丰富，而GC是总VEGF mRNA的主要来源。另一方面，TC是受体表达最多的卵泡区室。我们的结果表明，非优势卵泡维持着更高浓度的膜和可溶性VEGF受体的mRNA表达。另一方面，卵泡优势与sVEGFR1和sVEGFR2的mRNA表达降低有关，这可能有利于VEGF与VEGFR2结合，从而改善卵泡健康和发育。
