Stewart Jamie L, Canisso Igor F, Ellerbrock Robyn E, Mercadante Vitor R G, Lima Fabio S
Department of Veterinary Clinical Medicine, College of Veterinary Medicine, University of Illinois, Urbana, IL, USA; Department of Large Animal Clinical Sciences, Virginia-Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA.
Department of Veterinary Clinical Medicine, College of Veterinary Medicine, University of Illinois, Urbana, IL, USA.
Anim Reprod Sci. 2018 Oct;197:335-342. doi: 10.1016/j.anireprosci.2018.09.006. Epub 2018 Sep 6.
Nerve Growth Factor-β (NGF) is a seminal plasma protein that regulates sperm physiology in bulls, yet its production and association with fertility remain unclear. The objective of this study was to describe NGF distribution in bull accessory sex glands, quantify its seminal plasma concentrations, and determine its association with sire conception rates. Accessory sex glands were collected post-mortem from mature bulls (n = 3). Quantitative PCR and immunohistochemistry were performed in tissue samples. Pre-ejaculate and sperm-rich fraction of seminal plasma from Angus (n = 42) and sperm-rich fraction from Holstein (n = 10) bulls were collected by electroejaculation. Holstein (n = 76) and Jersey (n = 14) bulls were collected by artificial vagina, and those with available sire conception rate scores were allocated to: (1) negative/0 (n = 15); or (2) positive (n = 45). Seminal plasma NGF concentrations were measured using ELISA. Relative abundance of NGF mRNA was greatest in the vesicular, intermediate in ampulla, and lowest in prostate and bulbourethral glands (P ≤ 0.03). The most intense NGF staining was detected in the ampulla and vesicular glands (P < 0.05). Concentrations of NGF were greater in the sperm-rich fraction than in the pre-ejaculate and in samples collected by artificial vagina (P < 0.01). Seminal plasma NGF concentrations were greater in bulls with positive sire conception rate than those with negative/0 (P = 0.05). This study determined that NGF is produced in the ampulla and vesicular glands of bulls and is secreted into the sperm-rich fraction of the ejaculate. The positive association of NGF with bull fertility warrants further investigation.
神经生长因子-β（NGF）是一种精浆蛋白，可调节公牛的精子生理功能，但其产生及与生育力的关系仍不清楚。本研究的目的是描述NGF在公牛附属性腺中的分布，量化其精浆浓度，并确定其与种公牛受胎率的关系。从成熟公牛（n = 3）处死后采集附属性腺。对组织样本进行定量PCR和免疫组织化学分析。通过电刺激采得安格斯公牛（n = 42）的射精前精液和富含精子部分以及荷斯坦公牛（n = 10）的富含精子部分。通过人工阴道采集荷斯坦公牛（n = 76）和泽西公牛（n = 14）的精液，将有可用种公牛受胎率评分的公牛分为：（1）阴性/0（n = 15）；或（2）阳性（n = 45）。使用酶联免疫吸附测定法测量精浆中NGF的浓度。NGF mRNA的相对丰度在精囊腺中最高，壶腹部次之，在前列腺和尿道球腺中最低（P≤0.03）。在壶腹部和精囊腺中检测到最强的NGF染色（P < 0.05）。富含精子部分的NGF浓度高于射精前精液以及通过人工阴道采集的样本中的浓度（P < 0.01）。种公牛受胎率为阳性的公牛精浆中NGF浓度高于阴性/0的公牛（P = 0.05）。本研究确定，NGF在公牛的壶腹部和精囊腺中产生，并分泌到射精的富含精子部分。NGF与公牛生育力的正相关关系值得进一步研究。
