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To study the correlation of the gene expressions of Chk1 and Chk2 with sperm concentration and motility.According to sperm concentration and motility (percentage of progressively motile sperm), we divided 80 semen samples into four groups of equal number: normal control, oligozoospermia (OS), asthenospermia (AS), and oligoasthenozoospermia (OAS). We detected the sperm DNA fragmentation index (DFI) and viability and determined the expressions of Chk1 and Chk2 in the sperm by RT-PCR and Western blot.Statistically significant differences were not found in sperm DFI among the control, OS, AS, and OAS groups (21.24±6.93, 19.67±7.64, 21.52±6.92, and 19.28±11.55, P0.05), but observed in sperm concentration, progressive motility, and viability between the DFI30% and DFI ≤30% groups (P0.01). Compared with the normal control, sperm viability was remarkably decreased in the OS, AS, and OAS groups (［83.48±9.87］% vs ［63.86±9.16］%, ［50.45±16.99］%, and ［39.21±15.74］%, P0.05). RT-PCR showed remarkable differences among the control, OS, AS, and OAS groups in the relative expression level of Chk1 mRNA (0.73±0.22, 0.62±0.14, 1.03±0.39, and 0.92±0.071, P0.01), which was correlated positively with sperm concentration (b = 80.661, P0.01) but negatively with sperm motility (b = －19.275, P0.01), as well as in that of Chk2 mRNA (0.66±0.30, 0.27±0.09, 0.59±0.19, and 0.42 ± 0.11, P0.01), which was correlated negatively with sperm concentration (b = －90.809, P0.01) but positively with sperm motility (b = 27.507, P0.01). The relative expression levels of the Chk1 protein were significantly different among the four groups (0.63±0.05, 0.42±0.03, 1.13±0.08, and 0.87±0.07, P0.01), which was correlated positively with sperm concentration (b = 55.74, P0.01) but negatively with sperm motility (b =－22.649, P0.01), and so were those of the Chk2 protein (1.23±0.36, 0.37±0.16, 0.87±0.08, and 0.68±0.12, P0.01), which was correlated negatively with sperm concentration (b =－53.001, P0.01) but positively with sperm motility (b = 16.676, P0.01).Chk1 and Chk2 are significantly expressed in human sperm. In case of sperm DNA damage, up-regulated Chk1 expression may enhance sperm apoptosis and lead to asthenospermia, while increased Chk2 expression may inhibit spermatogenesis and result in oligospermia.目的： 研究精子中细胞周期检测点激酶1/2（Chk1和Chk2）基因的表达对精子浓度及活力的影响。方法： 将精液样本根据精子浓度和活力（前向运动精子百 分率）分为正常对照组、少精子症组、弱精子症组和少弱精子症组，每组20例。分别检测各组精子DNA碎片指数（DFI）、精子存活率，采用RT-PCR和Western印迹方法 分别检测各组精子Chk1、Chk2的表达。 结果： ①4组DFI分别为21.24±6.93、19.67±7.64、21.52±6.92、19.28±11.55，无显著差异 (P0.05)；4组精子存活率分别为（83.48±9.87）%、（63.86±9.16）%、（50.45±16.99）%、（39.21±15.74%），与正常对照组相比，其余3 组均有显著下降(P均0.05)；②DFI30%和DFI≤30%两组精子的浓度、活力和精子存活率之间的差异有统计学意义(P0.01)；③RT-PCR检测结果显示 ，4组Chk1 mRNA相对表达量分别为 0.73±0.22、0.62±0.14、1.03±0.39、0.92±0.071，各组间比较差异有显著性(P0.01)，其与精子浓度 呈正相关（b=80.661,P0.01），与精子活力呈负相关（b=－19.275,P0.01）；4组Chk2 mRNA相对表达量分别为 0.66±0.30、0.27±0.09、 0.59±0.19、0.42±0.11，各组间比较差异有显著性(P0.01)，其与精子浓度呈负相关（b=－90.809,P0.01），与精子活力呈正相关 （b=27.507,P0.01）。④Western印迹结果显示，4组Chk1 蛋白相对表达量分别为0.63±0.05、0.42±0.03、1.13±0.08、0.87±0.07，各组间 比较差异有显著性(P0.01)，其与精子浓度呈正相关（b=55.74,P0.01），与精子活力呈负相关（b=－22.649,P0.01）；4组Chk2 蛋白相对表达量分别为 1.23±0.36、0.37±0.16、0.87±0.08、0.68±0.12，各组间比较差异有显著性(P0.01)，其与精子浓度呈负相关（b=－53.001,P0.01） ，与精子活力呈正相关（b=16.676,P0.01）。结论： Chk1和 Chk2在人类精子中均有显著表达，在精子DNA出现损伤后，Chk1表达的增强可能促进了精子的凋亡 导致弱精子症，而Chk2表达的增强则可能抑制了精子的生成而导致少精子症。.

To study the effect of tea polyphenols (TP) on the apoptosis of germ cells in rats with experimental varicocele.Thirty-two adolescent male Wistar rats were randomly and equally divided into groups A (sham-operation), B (high-dose TP), C (low-dose TP), and D (experimental left varicocele). Experimental varicocele was induced by partial ligation of the left renal vein in the latter three groups of rats. The animals in groups A and D were fed with normal saline, while those in B and C with TP at 40 and 10 mg per kg per d, respectively, all for 4 weeks. Then, all the rats were sacrificed and the left testes harvested for determination of the expression of HIF-1, Bcl-2, Bax, CytC, and caspase-3 by immunohistochemistry and measurement of the apoptosis index (AI) of spermatogenic cells.The expression of Bcl-2 was higher in groups B and C than in D but lower than in A (P0.05), and lower in C than in B (P0.05). However, the expressions of HIF-1, Bax, CytC, and caspase-3 were lower in groups B and C than in D but higher than in A (P0.05), and higher in C than in B (P0.05). The AI of spermatogenic cells was the lowest in group A, higher in D than in the other groups but lower in B than in C (P0.05).TP can reduce the apoptosis of spermatogenic cells in a dose-dependent manner in varicocele rats.