Roudebush William E, Massey Joe B, Kort Hilton I, Elsner Carlene W, Toledo Andrew A, Mitchell-Leef Dorothy, Shapiro Daniel B
Reproductive Biology Associates, 1150 Lake Hearn Drive, Suite 400, Atlanta, Georgia 30342, USA.
J Assist Reprod Genet. 2004 Aug;21(8):297-300. doi: 10.1023/b:jarg.0000043703.73207.25.
Platelet-activating factor (PAF) plays a significant role in fertility. Preimplantation stage embryos produce PAF (ePAF) which is required for development. PAF's mechanism of action is receptor-mediated and its presence has been reported in the developing mouse and human embryo. Exposure of preimplantation stage mouse embryos results in higher implantation rates. However, the effect of such treatment on live-birth rates and birth weights has not been reported. Therefore, the objective the study was to determine the effect of exposing preimplantation mouse embryos to PAF on subsequent birth rate and weight.
Two-cell stage preimplantation stage mouse embryos exposed to PAF (10(-7) M) for 15 min prior to intraoviductal transfer.
Preimplantation stage embryos were recovered from eCG/hCG primed BDF1 female mice. Embryos were exposed to synthetic PAF (10(-7) M) for 15 min. PAF-treated embryos were transferred to the oviducts of pseudopregnant female CD-1 female mice. Superovulated and cultured BDF1 embryos not treated with PAF served as in vitro controls and naturally ovulated embryos with no collection/culture served as in vivo controls. Embryos were permitted to develop to term (18-21 days). The number of pups born per litter and litter weights subsequently were recorded.
A total of 160 BDF1 mouse embryos were collected, treated, and transferred (20 per CD-1 recipient) as described. There was a significant (P < 0.05) increase in the number of pups born to the PAF treatment group (56/80; 70%) as compared to the control group (44/80; 55%). There was also a significant difference (P < 0.05) in litter birth weights between the PAF (1.31 g/litter) and controls groups (1.25 g/litter). There was a significant difference (P < 0.05) in birth weights between the PAF treatment group and the in vivo group (1.51 g/litter). There was a significant difference in birth weights between the in vitro-control and in vivo groups (1.51 g/litter). There were no observational malformaties to pups born in any group.
Brief exposure of preimplantation stage embryos to PAF will result in a significant increase of delivery rates (pups/litter) as well as birth weights. However, the increase of birth weight was significantly below that found naturally. Additional studies are warranted to elucidate the mechanism of PAF's action in the preimplantation stage embryo and subsequent uterine development.
血小板活化因子（PAF）在生育过程中发挥着重要作用。植入前阶段的胚胎会产生PAF（胚胎PAF，ePAF），这是胚胎发育所必需的。PAF的作用机制是受体介导的，并且在发育中的小鼠和人类胚胎中均有报道。将植入前阶段的小鼠胚胎暴露于PAF会提高着床率。然而，这种处理对活产率和出生体重的影响尚未见报道。因此，本研究的目的是确定将植入前小鼠胚胎暴露于PAF对后续出生率和体重的影响。
在输卵管内移植前，将处于二细胞阶段的植入前小鼠胚胎暴露于PAF（10⁻⁷ M）15分钟。
从经eCG/hCG预处理的BDF1雌性小鼠中回收植入前阶段的胚胎。将胚胎暴露于合成PAF（10⁻⁷ M）15分钟。经PAF处理的胚胎被转移至假孕CD-1雌性小鼠的输卵管中。未用PAF处理的超排并培养的BDF1胚胎作为体外对照，未进行采集/培养的自然排卵胚胎作为体内对照。胚胎发育至足月（18 - 21天）。随后记录每窝出生的幼崽数量和窝重。
如前所述，共收集、处理并转移了160个BDF1小鼠胚胎（每个CD-1受体20个）。与对照组（44/80；55%）相比，PAF处理组出生的幼崽数量显著增加（P < 0.05）（56/80；70%）。PAF组（每窝1.31 g）与对照组（每窝1.25 g）的窝出生体重也存在显著差异（P < 0.05）。PAF处理组与体内组（每窝1.51 g）的出生体重存在显著差异（P < 0.05）。体外对照组与体内组的出生体重也存在显著差异（每窝1.51 g）。任何一组出生的幼崽均未观察到畸形。
将植入前阶段的胚胎短暂暴露于PAF会导致分娩率（每窝幼崽数）和出生体重显著增加。然而，出生体重的增加显著低于自然出生的情况。有必要进行进一步研究以阐明PAF在植入前阶段胚胎及后续子宫发育中的作用机制。
