Research Institute of Fish Culture and Hydrobiology, Faculty of Fisheries and Protection of Waters, University of South Bohemia in České Budějovice, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, Zátiší 728/II, 389 25, Vodňany, Czech Republic.
Neotropical Ichthyology Laboratory (LINEO), Department of Biology and Zootechny, Ilha Solteira School of Engineering, São Paulo State University, Monção Street, 226, Ilha Solteira, SP, 15385-000, Brazil.
Fish Physiol Biochem. 2020 Dec;46(6):1975-1980. doi: 10.1007/s10695-020-00848-y. Epub 2020 Jul 16.
The importance of reactive oxygen species and the antioxidant system in sperm biology has been recognized for different bony fishes but nothing is known in this regard for chondrichthyans. For the first time for cartilaginous fishes, the enzymatic antioxidant system was shown herein to be present in both fractions of sperm (spermatozoa and seminal fluid) collected from two different places (seminal vesicle and cloaca). In internally fertilizing freshwater ocellate river stingray, Potamotrygon motoro, the activity of superoxide dismutase and glutathione peroxidase was not changed upon sperm transition from the seminal vesicle to the cloaca. The activity of catalase was significantly increased for both sperm fractions at transition from the seminal vesicle to the cloaca (1.6 times for spermatozoa and 1.9 times for seminal fluid). The role of the sperm antioxidant system for different aspects of internal fertilization is discussed. The presented results are the initiatory step in uncovering the biochemical events of internal reproduction in Chondrichthyes.
活性氧物质和抗氧化系统在精子生物学中的重要性已在不同硬骨鱼类中得到认可，但在软骨鱼类中，这方面的知识还一无所知。本文首次报道了软骨鱼类的酶抗氧化系统存在于从两个不同部位（精囊和泄殖腔）收集的精子（精子和精液）的两个部分中。在内部受精的淡水黄貂鱼，Potamotrygon motoro 中，超氧化物歧化酶和谷胱甘肽过氧化物酶的活性在精子从精囊转移到泄殖腔时没有变化。过氧化氢酶的活性在精子从精囊转移到泄殖腔时，两个精子部分都显著增加（精子增加 1.6 倍，精液增加 1.9 倍）。讨论了精子抗氧化系统在内部受精的不同方面的作用。提出的结果是揭示软骨鱼类内部生殖生化事件的起始步骤。
