同型半胱氨酸对体外培养大鼠胚胎生长发育的影响

采用着床后体外全胚胎培养方法 ,观察同型半胱氨酸 (homocysteine,HCY)对大鼠胚胎生长发育的影响。将孕 9.5日龄大鼠胚胎移植于 HCY终浓度为 0、0 .15、1.5、2 .0、4.0、6 .0、8.0、10 .0 mm ol/L的全胚胎培养基中 ,于体外培养 48小时 ,观察 HCY对胚胎发育和器官形态分化的影响。结果显示 :HCY可影响大鼠胚胎在体外的生长发育 ,并呈现剂量 -效应关系 ;随着 HCY浓度的增加 ,卵黄囊体积减小、表面皱缩、血管减少及分化程度降低 ;胚胎生长发育迟缓并逐渐加重 ;同时伴有形态分化异常 ,出现多种畸形 ,主要畸形部位为神经系统和心脏等。上述结果提示 :HCY可能对胚胎有直接致畸作用 ,亦可能通过引起卵黄囊功能障碍而导致发育毒性。

Effects of homocysteine on post-implantation rat embryo cultured in vitro

In order to investigate the effect of homocysteine(HCY) on the development of rat embryos, the post-implantation whole embryo culture(WEC) technique was used. Neural plate stage(GD9.5) rat embryos were explanted in rat serum medium(immediately centrifugal serum, ICS) with D,L-HCY(0,0.15, 1.5,2.0,4.0,6.0,8.0,10.0 mmol/L), and cultured for 48 hours. The results showed that HCY did cause damage to embryonic development and the damages of HCY on embryos were characterized in a significant dose-response pattern. The minimum teratogenic dose of D,L-HCY was 0.15 mmol/L, the incidence of dysmorphogenic embryos was 8.33%. Significant inhibiting effects of HCY on yolk sac(including reduced yolk sac diameter, shriveled surface, small or defective yolk sac vessels) and embryonic growth and morpholological differentiation were apparent with increased HCY, while HCY were 4 mmol/L or more (P < 0.05). The abnormalities included neural tube defects, delayed cardiac tube formation, pericardial effusion, incomplete flexion, small or missing forelimb buds and irregular somites, etc. These findings suggested that HCY might exert a direct effect on embryos and a "double effect" both on yolk sac and embryos.