Induction of acrosome reaction of spermatozoa in Eriocheir sinensis by low temperature

Abstract

The effects of temperatures, durations of treatment, and derivations from spermatophores or spermaries on in vitro acrosome reaction of the spermatozoa in the Chinese mitten crab Eriocheir sinensis were investigated. The results showed that the different temperatures resulted in extremely significant differences (p \ 0.01) in the time of beginning acrosome reaction, the time of the maximum percentage of acrosome reaction, and the maximum percentage of acrosome reaction of the spermatozoa from spermatophores; and the low temperature (-20, -80°C and liquid nitrogen) induced acrosome reaction of more than 90% spermatozoa while 15 and 4°C didn't. Similar results occur in the spermatozoa, treated with -80°C for 15 min, from spermaries but the time of beginning acrosome reaction and the time of the maximum percentage of acrosome reaction were obviously longer than those from spermatophores. In conclusion, low temperature can induce acrosome reaction, which is a novel and efficient operating method of inducing acrosome reaction; the spermatozoa might be affected physiologically to capacitate with chilling. The study may be beneficial to new understandings of mechanism of acrosome reaction and provide the foundational material for artificial fertilization and breeding of this crab and other commercial aquatic crustaceans.

Notice of Retraction: Effects of Atrazine on the Acrosome Reaction of Spermatozoa in Eriocheir sinensis

“…At the studies of crustacean fertilization, many factors are considered to be essential for the induction of in vivo or in vitro AR in spermatozoa [2][3][4][5][6][7][8]. In the toxicology research, crustaceans have been chosen as test animals for evaluating the environmental contaminants effects [9].…”

Recent developments in male fertility evaluation, sperm cryopreservation and artificial fertilisation, and their potential application to decapod crustacean aquaculture

“…86,107 In the freshwater Chinese mitten crab (Eriocheir sinensis), AR reportedly can be induced by egg water, seawater, CaCl 2 solution or low temperature. 108,109 In addition, cryopreservation can also trigger AR in spermatozoa of E. sinensis 96 by directly promoting membrane fusion of the acrosomal cap, or by destruction of AR inhibiting and activation of AR promoting proteins. 96,110 Presently, efforts to quantify acrosome reaction in decapod crustaceans involve counting of acrosome-reacted vs. normal intact spermatozoa based on their morphological appearance using light microscopy.…”

“…Calcium ionophore A23187 can also induce the AR in decapod spermatozoa by increasing calcium influx into the cells 86,107 . In the freshwater Chinese mitten crab ( Eriocheir sinensis ), AR reportedly can be induced by egg water, seawater, CaCl 2 solution or low temperature 108,109 . In addition, cryopreservation can also trigger AR in spermatozoa of E .…”