人精浆中的胰岛素样生长因子及其结合蛋白的测定(在正常和输精管结扎男性间的比较研究)

Measurement of insulin-like growth factor (IGF) and IGF-binding protein in human seminal plasma:A comparison of Normal and vasectomized patients

目的 为探讨精浆中几种主要的胰岛素样生长因子 (IGFs)及其IGF 结合蛋白 (IGFBPs)的来源、存在特征和含量。方法 用免疫放射分析法 (IRMA) ,WesternLigandBlotting(WLB)和WesternImmunoblottig(WIB)法分析 18例正常和 15例输精管结扎男性精浆中的IGFs及其IGFBPs。结果 IRMA测定表明正常男性精浆中游离的IGF Ⅰ浓度 (3.3± 0 .6 μg/L)显著高于输精管结扎男性 (1.4± 0 .3μg/L) (P <0 .0 5 ) ;在正常和结扎男性精浆中游离的IGF Ⅱ浓度 (分别为 12 .2± 0 .2 μg/L和 12 .8± 0 .8μg/L)间和IGFBP 3浓度 (分别为 5 6 .5± 1.7μg/L和5 7.6± 1.4μg/L)间均无显著意义的差别 (P >0 .0 5 )。用WLB和WIB分析法证实了精浆中亦存在IGFBP 2、IGFBP 4和低分子量的IGFBP 3水解片段。结论 据推测精浆中的IGF Ⅰ可能主要来源于睾丸组织 ,而精浆中IGF Ⅱ和IGFBP 3不是主要从睾丸来源的 ;精浆中存在大量低分子量的IGFBP 3,提示在精浆中有对IGFBP 3特异的水解活性物质。

Objective To evaluate the sources,characteristics and contents of the insulin-like growth factor (IGFs) and IGF?binding protein (IGFBPs).Methods IGFs and IGFBPs in seminal plasma (SP) of 18 normal and 15 vasectomized patients were analysed using IRMA,western ligand blotting (WLB) and western immunoblotting (WIB).Results From IRMA shown that free IGF?Ⅰ concentrations in SP of normal men (3.3±0.6 μg/L) were significantly higher than concentrations of vasectomized patients (1.4±0.3 μg/L)( P <0.05).The concentrations of IGF?Ⅱ and IGFBP?3 in SP do not differ significantly between normal and vasectomized patients (12.2±0.2 μg/L and 12.8±0.8 μg/L;56.5±1.7 μg/L and 57.6±1.4 μg/L,respectively),( P <0.05).The IGFBP?2,IGFBP?4 and Low mol wt IGFBP?3 fragments in SP on WLB or WIB were also domonstrated.Conclusions The testicular contribution of SP IGF?Ⅰ may be in major,but the testicular contribution of SP IGF?Ⅱ and IGFBP?3 is probably in minor.The low molecular weight IGFBP?3 fragments suggest that SP contains special proteolytic activity.