Analysis of the motility parameters of in vitro hyperactivated hamster spermatozoa

Abstract

Golden hamster cauda epididymal spermatozoa under in vitro capacitating conditions exhibited time-dependent transformation of motility pattern, and the frequency of occurrence of a particular motility type was found to be dependent on the depth of the motility chamber used. The nonhyperactivated spermatozoa with planar motility were the most predominant at 0 hr irrespective of the depth of the motility chamber. But spermatozoa with the helical motility pattern were not detectable up to 6 hr when the Makler chamber was used, whereas in both the slide chamber and cannula, by 2 hr such spermatozoa constituted 90% of the total spermatozoa. However, by 6 hr the hyperactivated circular moving spermatozoa were the predominant type in all the chambers. Sperm motility chamber depths were also found to effect the motility parameter values of hamster spermatozoa, but this effect was also found to be dependent on the type of motility. Increase in chamber depth did not alter any of the motility parameter values of spermatozoa with hatchet type of motility and only increased the amplitude of lateral head displacement (ALH) in planar type. But in spermatozoa with the helical type of motility, an increase in chamber depth increased the progressive velocity (VSL), path velocity (VAP), curvilinear velocity (VCL), straightness (STR), linearity (LIN), and ALH. In spermatozoa with the circular type of motility, an increase in VSL, VAP, VCL, and ALH was also observed, but STR and LIN decreased. The hyperactivated spermatozoa could be distinguished from the nonhyperactivated spermatozoa because the former were swimming in circles, had low progressive velocity, decreased straightness and linearity of path, and also exhibited an increase in the amplitude of lateral head displacement compared to the nonhyperactivated spermatozoa. Further, the spermatozoa with helical motility could be differentiated from the nonhyperactivated, circular, and hatchet spermatozoa in that they had the highest VSL, VAP, VCL, and ALH. Spermatozoa with hatchet movement were slow and exhibited very low STR and LIN. Thus the motility parameters could be used to distinguish the nonhyperactivated and hyperactivated distal cauda epididymal spermatozoa.