Abstract
Hyperactivation and acrosome reaction are prerequisite
steps for sperm to be able to fertilize an
oocyte. In mammals, hyperactivation is defined as
a movement pattern seen in spermatozoa at the site
and time of fertilization. The objectives of the present
experiments were to analyze the process of
hyperactivation and to investigate its relationship
with progesterone evoked intracellular calcium
concentration ([Ca2+]i) increase and their implications
with infertility.
After capacitation the sperm from patients,
when compared with donor’s sperm, showed
decreased percentage of hyperactivated sperm,
molitily, progressive motility, and curvilinear
velocity (VCL). On the other hand, the linearity
(LIN) was increased. Amplitude of lateral head
displacement (ALH) and [Ca2+]i increase (peak
and plateau from baseline) showed good correlation
in patients with infertility.
These data suggest that impaired hyperactivation
might be involved in the pathophysiology of infertility.
