Adebayo A O, Akinloye A K, Ihunwo A O, Taiwo V O, Oke B O
Department of Veterinary Anatomy, College of Veterinary Medicine, Federal University of Agriculture, Abeokuta, Nigeria.
School of Anatomical Sciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
J Microsc Ultrastruct. 2019 Jan-Mar;7(1):14-18. doi: 10.4103/JMAU.JMAU_28_18.
In furthering the understanding of the process of spermatogenesis in the greater cane rat, this study describes the ultrastructural spermiogenic transformation and acrosomal formation in the testes of this hystricomorphic rodent that is currently undergoing domestication in parts of West Africa.
Testicular samples were obtained from ten sexually mature cane rats that were perfused-fixed using Karnovsky's fixative (phosphate buffered 2% paraformaldehyde - 2.5% glutaraldehyde fixative at pH 7.4). The samples were processed for ultrastructural analysis and examined under the transmission electron microscope.
The testes of the cane rat showed uniqueness in its cellular associations and the ultrastructure of the spermatogenic cells especially in the formation of the acrosome. The spermatid differentiation and acrosomal formation occurred in 12 steps with the first three steps being the phase and the next three steps making up the phase. While the three steps that follow constitute the phase, the last 3 steps make up the phase. At the cap and acrosomal phases, the entire acrosomal system comprising the vesicle and granule covers the head of the spermatids with no clear indentation of the nuclear surface by the formed acrosome. Furthermore, elongated spermatids at the maturation phase contained abundance of nuclear vacuoles.
This work has not only provided information that will further the understanding of spermatogenesis but also aid the understanding of acrosomal reaction in the reproduction of the greater cane rat.
为了进一步了解大蔗鼠的精子发生过程，本研究描述了这种目前正在西非部分地区进行驯化的豪猪型啮齿动物睾丸中的超微结构精子发生转化和顶体形成。
从10只性成熟的蔗鼠获取睾丸样本，使用卡诺夫斯基固定液（pH 7.4的磷酸盐缓冲2%多聚甲醛 - 2.5%戊二醛固定液）进行灌注固定。对样本进行超微结构分析处理，并在透射电子显微镜下观察。
蔗鼠的睾丸在细胞关联以及生精细胞的超微结构方面表现出独特性，尤其是在顶体形成方面。精子细胞分化和顶体形成分12个步骤进行，前三个步骤为 期，接下来的三个步骤构成 期。随后的三个步骤构成 期，最后三个步骤组成 期。在帽期和顶体期，由囊泡和颗粒组成的整个顶体系统覆盖精子细胞头部，形成的顶体未使核表面出现明显凹陷。此外，成熟阶段的延长型精子细胞含有大量核空泡。
这项工作不仅提供了有助于进一步了解精子发生的信息，还有助于理解大蔗鼠繁殖过程中的顶体反应。
