Roudebush William E, Purnell Elissa T, Stoddart Neil R, Fleming Steven D
Reproductive Biology Associates, Atlanta, Georgia 30342, USA.
J Assist Reprod Genet. 2002 Feb;19(2):72-8. doi: 10.1023/a:1014443630722.
Preimplantation embryos synthesize platelet-activating factor (PAF) and this embryo-derived PAF is required for development. PAF's signal transduction is receptor-mediated and PAF-receptor mRNA is present in early embryos. The study objective was to determine the relationship between PAF production and PAF-receptor mRNA expression levels in mouse preimplantation embryos.
Embryo-derived PAF levels were determined by radioimmunoassay. Embryonic PAF-receptor mRNA levels were determined by semiquantitated reverse transcription-polymerase chain reaction.
Embryonic-PAF increased as time progressed at a relatively constant rate (1.4-1.9 x) except between the eight- and morula-cell stages where levels increased sevenfold. Embryonic PAF-receptor expression was highest at the two-cell stage and decreased steadily until the morula stage before increasing again. Regression analysis of embryo-derived PAF on PAF-receptor expression does not demonstrate a significant relationship.
PAF-receptor expression (mRNA) levels decrease, while embryo-derived PAF levels decrease, as the preimplantation embryo develops. Embryonic-PAF and PAF-receptor mRNA expression do not appear related. Therefore, embryonic-PAF does not appear to regulate expression of its own receptor in vitro. The data provide a clue to the complicated cell signaling system involving PAF production and receptor expression that may help our understanding of developmental events.
植入前胚胎可合成血小板活化因子(PAF),且胚胎来源的PAF是胚胎发育所必需的。PAF的信号转导是由受体介导的,并且PAF受体mRNA存在于早期胚胎中。本研究的目的是确定小鼠植入前胚胎中PAF产生与PAF受体mRNA表达水平之间的关系。
通过放射免疫测定法测定胚胎来源的PAF水平。通过半定量逆转录-聚合酶链反应测定胚胎PAF受体mRNA水平。
胚胎PAF随着时间的推移以相对恒定的速率增加(1.4 - 1.9倍),但在八细胞期和桑葚胚期之间水平增加了七倍。胚胎PAF受体表达在二细胞期最高,并持续下降直至桑葚胚期,然后再次上升。对胚胎来源的PAF与PAF受体表达进行回归分析未显示出显著关系。
随着植入前胚胎的发育,PAF受体表达(mRNA)水平下降,而胚胎来源的PAF水平也下降。胚胎PAF和PAF受体mRNA表达似乎没有关联。因此,胚胎PAF在体外似乎不调节其自身受体的表达。这些数据为涉及PAF产生和受体表达的复杂细胞信号系统提供了线索,这可能有助于我们理解发育事件。