Second Military Medical University, Shanghai, China.
J Assist Reprod Genet. 2010 Sep;27(9-10):525-31. doi: 10.1007/s10815-010-9451-2. Epub 2010 Aug 14.
To investigate the relationship between oxytocin (OT) and male infertility, serum OT baseline concentration and oxytocin receptor (OTR) gene expression in fertile and infertile men were investigated.
Twenty obstructive azoospermia patients, twenty five idiopathic asthenozoospermia patients, twenty idiopathic oligozoospermia patients and twenty healthy subjects were taken into consideration. Serum OT baseline concentration was determined by radioimmunoassay. Moreover, serum concentration of luteinizing hormone (LH), follicle-stimulating hormone (FSH) and testosterone (T) were determined by chemoluminescence to evaluate the correlation with OT. OTR gene promotor and OTR mRNA expressions were determined by polymerase chain reaction and reverse transcriptase-polymerase chain reaction, respectively. OTR protein expression was also performed by Western Blot.
Serum OT baseline concentrations in infertile groups were significantly higher than in fertile group (F0.05/2(2,82) = 8.29, p < 0.001). Serum baseline concentration of OT was not correlated with that of LH, FSH and T. There was no significant difference in gene sequences of OTR gene promotor and OTR mRNA when comparing infertile patients with fertile. Human OTR was in the form of oligomers and monomers, and the oligomers were in the majority containing tetramers and hexamers. Monomer expression was significantly higher in idiopathic asthenozoospermia and idiopathic oligozoospermia than that in obstructive azoospermia and control group (F0.05/2(2,82) = 115.50, p < 0.001). There was no significant difference in oligomer expression between different groups, but 20% of idiopathic asthenozoospermia cases showed a decrease.
Significantly different OT baseline concentrations and OTR expressions between fertile and infertile men strongly suggest that OT/OTR system is likely to be linked with male infertility, providing new insights into the pathogenesis and treatment of male infertility.
探讨催产素（OT）与男性不育的关系，研究了生育能力正常男性和不育男性的血清 OT 基础浓度和催产素受体（OTR）基因表达。
共纳入 20 例梗阻性无精子症患者、25 例特发性弱精子症患者、20 例特发性少精子症患者和 20 例健康对照者。采用放射免疫法测定血清 OT 基础浓度。此外，采用化学发光法测定血清黄体生成素（LH）、卵泡刺激素（FSH）和睾酮（T）浓度，以评估与 OT 的相关性。采用聚合酶链反应和逆转录聚合酶链反应分别测定 OTR 基因启动子和 OTR mRNA 表达，采用 Western blot 测定 OTR 蛋白表达。
不育组血清 OT 基础浓度明显高于生育组（F0.05/2(2,82) = 8.29，p < 0.001）。OT 血清基础浓度与 LH、FSH 和 T 无相关性。不育患者与生育组相比，OTR 基因启动子的基因序列和 OTR mRNA 无明显差异。人 OTR 以寡聚体和单体的形式存在，其中寡聚体以四聚体和六聚体为主。单体表达在特发性弱精子症和特发性少精子症患者中明显高于梗阻性无精子症和对照组（F0.05/2(2,82) = 115.50，p < 0.001）。不同组间寡聚体表达无明显差异，但 20%的特发性弱精子症患者表达下降。
生育能力正常男性和不育男性的 OT 基础浓度和 OTR 表达存在显著差异，强烈提示 OT/OTR 系统可能与男性不育有关，为男性不育的发病机制和治疗提供了新的思路。
