环磷酰胺对大鼠早期胚胎发育里程的影响

Effects of cyclophosphamide on early rat embryo developmental landmark

目的：为探索烷化剂对哺乳动物早期胚胎发育里程的影响及其可能的机制。方法：孕大鼠第３ 天ｉｐ 环磷酰胺（Ｃｙｃ １０ 、２０ 、４０ｍｇ／ｋｇ） ，孕第４ 天评价胚胎的胚胎化作用，胚胎发育时相，及蜕变胚胎率；同时显微外科分离胚胎内细胞团及滋养层细胞，评价两群细胞受损情况。结果：在Ｃｙｃ １０ｍｇ／ｋｇ 时，胚胎的胚泡化作用，胚胎发育时相均未受明显影响；４０ｍｇ／ｋｇ 时，蜕变胚胎率明显提高。胚泡化率及胚胎细胞数呈剂量依赖性减少，其中内细胞团细胞减少尤甚。结论：Ｃｙｃ 在未引起早期胚胎蜕变率显著增加时，可影响细胞周期，但不影响发育里程；高剂量时。

OBJECTIVE:To study the effects of alkylate on the developmental mileage of early mammal embryos and the possible mechanism.METHOD:Pregnant rats on d3 of gestation were given ip cyclophosphamide(Cyc)10,20,40 mg/kg .On d4,the blastulation,the developmental phase of embryos and the frequency of degenerated blastocysts were evaluated.Inner cell mass(ICM)and trophectoderm(TE)were isolated by immunosurgery and the damages on the two cell lineages were evaluated.RESULTS:In Cyc 10mg/kg group,no significant difference were observed on the blastulation and the developmental phase of embryos.In Cyc 40mg/kg group,the frequency of degenerated blastocysts was markedly increased,while the frequency of blastulation and the cell number of blastocysts were decreased in a dose dependent manner.The reduction was more severe in ICM.CONCLUSION:When Cyc had not induced no significant increase in the frequency of degenerated blastocysts,the cell cycle was influenced by Cyc,but the developmental landmark was not changed.Marked effect on the developmental mileage and marked increase in the frequecy of degenerated blastocysts were obviously observed in Cyc 40mg/kg.