二氧化乙烯基环己烯致大鼠早发性卵巢功能不全模型的给药剂量探讨

Dosage of 4-Vinylcyclohexene Diepoxide in Induction of Premature Ovarian Insufficiency in Rats

目的:通过比较二氧化乙烯基环己烯(VCD)不同剂量和不同停药时间对雌性大鼠生殖内分泌水平的影响,以探索VCD构建早发性卵巢功能不全(POI)大鼠模型有效、稳定及安全的给药剂量。方法:将动情周期规律的SD大鼠随机分为3组,分别为空白组、VCD低、高剂量组(80、160 mg·kg^(-1)·d^(-1)),每组24只。药物干预后,分别于干预后第15天和第45天取材,检测大鼠的一般情况、动情周期紊乱率、血清激素水平、卵巢组织形态学、卵泡计数、妊娠结局、转化生长因子-β(TGF-β)和Smad2/3蛋白及mRNA表达。结果:与空白组比较,VCD低剂量组大鼠动情周期紊乱率、血清促卵泡激素(FSH)、促黄体生成激素(LH)、雌二醇(E_(2))水平差异无统计学意义;卵巢组织受损,原始卵泡和初级卵泡在第15天显著减少(P<0.01),在第45天进一步出现次级卵泡(P<0.01)和窦卵泡(P<0.05)数量明显减少;产崽数在第15天明显减少(P<0.05),但在第45天差异无统计学意义;TGF-β蛋白水平在第15天(P<0.05)和第45天(P<0.01)升高;Smad2/3在第45天显著升高(P<0.01);TGF-β和Smad2/3mRNA水平在第45天升高(P<0.05)。与空白组比较,VCD高剂量组大鼠动情周期紊乱率在第45天升高(P<0.01);血清FSH、LH明显升高,E_(2)明显下降(P<0.05,P<0.01);卵巢组织受损,各级卵泡下降趋势同VCD低剂量组;产崽数在第15天和第45天均明显下降;TGF-β和Smad2/3蛋白水平升高(P<0.05,P<0.01),TGF-β mRNA在第45天明显升高(P<0.05)。结论:VCD高剂量是VCD构建POI大鼠模型的理想剂量,具有有效性、稳定性和安全性。

Objective To compare the effects of different doses and withdrawal time of 4-vinylcyclohexene diepoxide(VCD)on the reproductive endocrine levels of female rats,and to explore the effective,stable,and safe dosage of VCD for constructing a premature ovarian insufficiency(POI)rat model.Method SD rats with regular estrous cycles were randomly divided into three groups:blank group,low-dose VCD group(80 mg·kg^(-1)·d^(-1)),and high-dose VCD group(160 mg·kg^(-1)·d^(-1)),with 24 rats in each group.After drug intervention,samples were collected on the 15th day(D15)and the 45th day(D45)after intervention.The general condition,rate of estrous cycle disturbance,serum hormone levels,ovarian histomorphology,follicle count,pregnancy outcome,and the protein and mRNA expression of transforming growth factor(TGF)-βand Smad2/3 were assessed.Result Compared with the blank group,the low-dose VCD group showed no significant differences in the rate of estrous cycle disturbance or serum follicle-stimulating hormone(FSH),luteinizing hormone(LH),and estradiol(E_(2))levels.Ovarian tissue was damaged.Specifically,the number of primordial and primary follicles decreased on D15(P<0.01),and the number of secondary follicles(P<0.01)and antral follicles(P<0.05)further decreased on D45.The litter number decreased on D15(P<0.05),but there was no significant difference on D45.Furthermore,TGF-βprotein levels increased on D15(P<0.05)and D45(P<0.01).The Smad2/3 levels increased on D45(P<0.01),and TGF-βand Smad2/3 mRNA levels increased on D45(P<0.05).Compared with the results in the blank group,the disturbance rate of the estrous cycle increased on D45 in the high-dose VCD group(P<0.01).The serum of FSH and LH increased(P<0.01),while E_(2) decreased(P<0.05).Ovarian tissue was damaged,and the downward trend of follicles at all levels was similar to that in the low-dose VCD group.The litter number significantly decreased on D15 and D45.TGF-βand Smad2/3 protein levels increased(P<0.05,P<0.01),and TGF-βmRNA increased on D45(P<0.05).Conclusion High-dose VCD is an ideal method for constructing a POI rat model,being effective,stable,and safe.