Papageorgiou K V, Grivas I, Chiotelli M, Panteris E, Papaioannou N, Nauwynck H, Kritas S K
Department of Microbiology and Infectious Diseases, School of Health Sciences, Aristotle University of Thessaloniki, 54124, Greece.
Laboratory of Anatomy Histology, and Embryology, School of Health Sciences, Aristotle University of Thessaloniki, 54124, Greece.
Anat Histol Embryol. 2017 Feb;46(1):58-64. doi: 10.1111/ahe.12234. Epub 2016 May 19.
Myelination, the ensheathing of neuronal axons by myelin, is important for the proper function of both central and peripheral nervous systems. Various studies have investigated the quantitative parameters of myelination in certain species. Pigs are among the species of which their use as laboratory animals in neuroscience research increased the past few decades. However, there is limited data regarding the myelination process in the pig. Moreover, the maxillary nerve is crucial for Pseudorabies Virus (PrV) neuropathogenesis. In this context, a quantitative analysis of various myelination parameters of the maxillary nerve was performed, during the first 5 weeks of porcine post-natal development, the time period, which exhibits the highest interest for PrV neuropathogenesis. The evaluation was conducted in four groups of uninfected pigs, at the time of birth (group 0w), at the age of 1 week (group 1w), 3 weeks (group 3w) and 5 weeks (group 5w), using toluidine blue staining, immunofluorescence and electron microscopy. Axon and fibre diameter, perimeter and surface, myelin sheath thickness and g-ratio were measured on histological sections transverse to the longitudinal axis of the maxillary nerve. The thickness of myelin sheath was 0.76 μm for group 0w, 0.94 μm for group 1w, 0.98 μm for group 3w and 1.03 μm for group 5w. The g-ratio was 0.529, 0.540, 0.542 and 0.531 for the respective animal groups. The results of this study contribute to the understanding of the myelination process in the pig will be used for the study of PrV effects on the myelination development of newborn piglets' maxillary nerve and may shed new light to their vulnerability to the virus.
髓鞘形成，即髓磷脂对神经元轴突的包裹，对中枢和外周神经系统的正常功能都很重要。各种研究已经调查了某些物种中髓鞘形成的定量参数。猪是过去几十年中在神经科学研究中作为实验动物使用增加的物种之一。然而，关于猪髓鞘形成过程的数据有限。此外，上颌神经对伪狂犬病病毒（PrV）神经发病机制至关重要。在此背景下，在猪出生后的前5周（这是对PrV神经发病机制最感兴趣的时间段），对上颌神经的各种髓鞘形成参数进行了定量分析。评估在四组未感染的猪中进行，分别在出生时（0周组）、1周龄（1周组）、3周龄（3周组）和5周龄（5周组），使用甲苯胺蓝染色、免疫荧光和电子显微镜。在与上颌神经纵轴垂直的组织学切片上测量轴突和纤维直径、周长和表面积、髓鞘厚度和g比值。0周组的髓鞘厚度为0.76μm，1周组为0.94μm，3周组为0.98μm，5周组为1.03μm。相应动物组的g比值分别为0.529、0.540、0.542和0.531。本研究结果有助于理解猪的髓鞘形成过程，将用于研究PrV对新生仔猪上颌神经髓鞘发育的影响，并可能为其对该病毒的易感性提供新的线索。
