Hyperactivated motility patterns of ram spermatozoa recovered from the oviducts of mated ewes

Abstract

The contents of the oviducts of ewes were recovered by flushing with small volumes of culture medium, 22'/2-241/4 hr after mating. The ampulla was flushed separately from the uterotubal junction and isthmus. Among the motile spermatozoa recovered, a proportion exhibited "hyperactivated" motility, also known as "activated", or "whiplash" motility. This was characterized by increased flexion of the neck, increased amplitude of the flagellar waves, and marked asymmetry of beat. Two types of hyperactivation appeared: in the first, spermatozoa swam in a repetitive, nonprogressive circling pattern and appeared to have intact acrosome caps; in the second, the spermatozoa showed a propensity to stick to glass by the equatorial segment and most had modified or missing acrosome caps. The proportions of motile spermatozoa exhibiting hyperactivation were greatest in the ampullae, as were the proportions with modified or absent acrosomes. Hyperactivation is a capacitation-associated phenomenon that has now been reported for one or more species from seven orders of eutherian mammals. It may well be a universal aspect of the prefertilization behavior of mammalian spermatozoa and is probably of advantage to the fertilizing spermatozoon within the oviduct.

Changes in the motility pattern of human spermatozoa during in vitro incubation.

“…This highcurvature and sometimes thrashing motility was named hyperactivation (Yanagimachi 1970(Yanagimachi , 1981. Since that first report, similar phenomena have been Received October 7, 1987; revision accepted for publication December 11, 1987 (Lambert 1981), dolphin (Fleming et al 1982) and sheep (Cummins 1982) as well. The occurrence of hyperactivation in human spermatozoa has been more difficult to study, since the acrosome reaction cannot be directly assessed, capacitation must be carried out in vitro and homologous fertilization cannot be studied experimentally.…”

Aggregation of Human Sperm at Higher Temperature Is Due to Hyperactivation

“…The percentage of hyperactive sperm was measured using the sort fraction module [3]. Hyperactive motility is characterized by star-spin or whiplash movement with wide amplitude of lateral head displacement, high curvilinear velocity, and low or nonlinear direction distinctly different from helical movement [3,8,10,11,17,19,21].…”

Presence of follicular fluid in the porcine oviduct and its contribution to the acrosome reaction

“…It may help prornote sperm transport from the isthmus to the ampulla of the oviduct (Cummins, 1982) and it has been postulated that hyperactivation gives the sperm the thrust it requires for penetration of the cumulus oophorus and then the egg.…”