Wilson M J, Ruhland A R, Pryor J L, Ercole C, Sinha A A, Hensleigh H, Kaye K W, Dawkins H J, Wasserman N F, Reddy P, Ahmed K
Minneapolis VA Medical Center, University of Minnesota Cancer Center, University of Minnesota, Minneapolis 55417, USA.
J Urol. 1998 Nov;160(5):1905-9.
A number of peptidases which can metabolize certain bioactive peptides and growth factors have been identified in seminal plasma. Our goal in this study was to determine molecular properties and the tissue source(s) for one of these peptidases, dipeptidylpeptidase IV (DPP IV), in human seminal plasma.
We measured the activities of DPP IV with the dipeptide glycylprolyl-p-nitroanalide and its molecular forms using immunoblotting of seminal plasmas of men who were vasectomized or with different sperm concentrations, and in prostatic and seminal vesicle secretions of men undergoing prostatic surgery.
DPP IV in seminal plasma of vasectomized men was a membrane associated dimer comprised of subunits of approximately 110 kDa. Its activity did not differ in seminal plasmas of vasectomized, azoospermic, oligozoospermic and normozoospermic men indicating no correlation with the concentration of sperm originally present in the semen. The DPP IV antigen (CD -26) and enzymic activity were present in prostatic secretion, but absent from that of the seminal vesicles. These data indicate that the prostate gland is the primary source of DPP IV activity in seminal plasma. There was little variation in its activities in repeat seminal plasma samples from the same individual, and there was no change in its activity with age to 50 years.
DPP IV in seminal plasma was derived from the prostate gland and it may be useful as a bioindicator of prostate function and/or disease with age in men.
已在精浆中鉴定出多种可代谢某些生物活性肽和生长因子的肽酶。本研究的目的是确定人精浆中这些肽酶之一——二肽基肽酶IV（DPP IV）的分子特性和组织来源。
我们使用二肽甘氨酰脯氨酰对硝基苯胺测定了DPP IV的活性，并通过对接受输精管切除术或精子浓度不同的男性的精浆进行免疫印迹分析，以及对接受前列腺手术的男性的前列腺和精囊分泌物进行免疫印迹分析，来确定其分子形式。
输精管切除术后男性精浆中的DPP IV是一种与膜相关的二聚体，由约110 kDa的亚基组成。在输精管切除术后的男性、无精子症患者、少精子症患者和正常精子症患者的精浆中，其活性没有差异，这表明与精液中最初存在的精子浓度无关。DPP IV抗原（CD -26）和酶活性存在于前列腺分泌物中，但在精囊分泌物中不存在。这些数据表明，前列腺是精浆中DPP IV活性的主要来源。同一个体重复的精浆样本中其活性几乎没有变化，并且在50岁之前其活性不会随年龄变化。
精浆中的DPP IV来源于前列腺，它可能作为男性前列腺功能和/或随年龄增长的疾病的生物指标。
