单纯性尿道下裂患者Ⅱ型5α-还原酶的活性评估

Assessment of typeⅡ5 alpha-reductase activitiy in boys with isolated hypospadias

目的测定单纯性尿道下裂患者Ⅱ型5α-还原酶的活性。方法2005年4～9月在该院就诊患者,其中单纯性尿道下裂患者22人,对照组为包皮环切患者25人。从包皮组织制备出作为Ⅱ型5α-还原酶载体的粗微粒体悬液,根据分光光度计连续测定NADPH的OD340nm值的时间变化曲线来折算该酶的活性。结果22例单纯性尿道下裂患者Ⅱ型5α-还原酶活性为(0.3014±0.0054)μmol/(L·min),25例对照组该酶活性为(0.3065±0.0032)μmol/(L·min),前者的酶活性略低于后者,两者的酶活性结果经t检验差异无显著性。结论单纯性尿道下裂患者和正常人比较,Ⅱ型5α-还原酶的活性无明显变化。此外,从包皮组织中提取Ⅱ型5α-还原酶,根据NADPH的OD值的时间变化曲线来检测该酶的活性,具有简便快捷和经济实用的特点。

[Objective] To measure the type Ⅱ 5 alpha-reductase activity in boys with isolated hypospadias. [Methods] From April 2005 to September 2005, the type Ⅱ 5 alpha-reductase activity was measured in foreskin specimens of 22 boys with isolated hypospadias and was compared to that of healthy control subjects. A spectrophotometer was used to measure the changes of the product NADPH by monitoring the variation in absorbance at 340 nm. [Results] The activity of type Ⅱ 5 alpha-reductase did not show any significant difference between tissues acquired from boys with isolated hypospadias and normal tissues obtained from the control group （0.3014±0.0054） vs. （0.3065±0.0032） μmol/L·min）. Compared to the control group, the type Ⅱ 5 alpha-reductase activity was slightly lower in the patient group. [Conclusion] There is no difference of type Ⅱ 5 alpha-reductase activity in the foreskin specimens between patients with isolated hypospadias and the control group. This method of measuring type Ⅱ 5 alpha-reductase activity has the advantages of being easy to perform.