不同剂量环磷酰胺建立小鼠少精子症模型

Establishment of oligosperm model by different doses of cyclophosphamide in mice

目的探讨用环磷酰胺建立小鼠少精子症动物模型的最佳诱导剂量。方法选择雄性小鼠120只随机分4组，连续5d分别以生理盐水（对照组），不同剂量的环磷酰胺（每日100、80、60mg／kg体重）于腹腔内注射，在不同时段分批处死各组小鼠，检测血清T、LH水平，一侧睾丸匀浆后测定（丙二醛）MDA含量，另一侧睾丸切片苏木素-伊红（HE）染色进行生精小管上皮层次和间质细胞计数。结果剂量每日为80mg／kg体重小鼠成模后死亡率为16．7％，血清T[30d：（1．38±0．31）；45d：（1．15±0．26）]及T／LH比值[30d：（0．163±0．014）；45d：（0．127±0．023）]于诱导后第30天出现显著下降（P均〈0．05），而诱导后睾丸组织内MDA含量[15d：（2．70±0．41）；30d（2．71±0．36）；45d：（2．67±0．43）]维持高水平（P均〈0．05），生精上皮层次[15d：（4．75±0．82）；30d：（3．60±0．49）；45d：（3．74±0．43）]和间质细胞[15d：（9．65±0．75）；30d：（14．05±0．67）；45d：（8．49±0．72）]均显著减少（P均〈0．01）并稳定于低水平，模型稳定，死亡率适当；每日60mg／kg体重组小鼠血清T及T／LH比值于不同时段并未出现明显变化（P〉0．05），且睾丸组织内MDA含量、生精上皮层次和间质细胞计数在30d后有所恢复，模型不稳定；每日100mg,／kg体重组死亡率为30．0％，死亡率过高。结论腹腔内注射环磷酰胺建立小鼠少精子症模型的最佳剂量为每日80mg／kg体重。

Objective To explore the optimal dosage of cyclophosphamide for inducing oligosperm in mouse model. Methods One hundred and twenty experimental male mice were randomly divided into 4 groups,which were respectively treated by intraperitoneal injection of normal saline （control） and different doses of cyclophosphamide （ 100,80,60 mg/kg, day） continuously for 5 days. The mice were killed in batches at different time points. The serum testosterone （T） and luteotrophic hormone （LH） levels were measured. A suspension was made from the testis of one side for malondialdehyde （MDA） level analysis,while the testis of other side was sliced up and stained by HE method to detect the count of Leydig cells and the layers of spermatogenetic epithelia. Results The mortality rate of mice in 80 mg/kg, day cyelophosphamide group was 16.7% , and T level [ at 30th day ： （ 1.38±0.31 ） ;45th day ： （ 1.15 ±0.26 ） ] and T/LH ratio [ at 30th day： （0. 163 ±0. 014） ;45th day： （0. 127±0. 023） ] were significantly decreased （all P 〈 0.05 ） at 30th day after induction;The concentration of MDA [ at 15th day： （2.70±0.41） ;30th day：（2.710.36） ;45th day： （2.67 ±0.43） ] was maintained at a high level （all P 〈0.05） during the 45 days ; Number of Leydig＇ s ceils [ at 15th day ： （ 9.65±0.75 ） ; 30th day ： （ 14.05± 0.67 ） ; 45th day ： （ 8.49±072） ] and layers of spermatogenetic epithelia [ at 15th day： （4.75 ±0.82） ;30th day ： （ 3.60 ± 0.49 ） ;45th day ： （ 3.74 ± 0.43 ） ] were significantly decreased （ all P 〈 0.01 ） and stabilized in a low level. The induced model was stable and the mortality rate was acceptable. In the 60 mg/kg, day eyclophosphamide group, the T level and T/LH ratio had no significant change （P 〉 0.05 ）, and the concentration of MDA, number of Leydig＇ s cell and layers of spermatogenetic epithelia recovered at 30th day after induction. The induced model was unstable. The mortality rate in 100 mg/kg, day cyclophosphamide group was 30% and unacceptable. Conclusion The optimal dosage of eyclophosphamide for inducing oligo- sperm in mouse model was 80 mg/kg, day.