The role of Ca2+ and protein kinase C in the acrosome reaction of giant panda (Ailuropoda melanoleuca) spermatozoa.
Fresh semen was collected from adult male giant pandas and the role of Ca2+, Ca2+ ionophore A23187 and protein kinase C (PKC) in sperm motility and acrosome reaction (AR) was assessed by lens culinaris agglutinin conjugated with fluorescein isothiocyanate (FITC-LCA) labeling and transmission electron microscopy. The AR in giant panda spermatozoa was characterized by vesiculation of the outer acrosomal membrane through its invagination. Both the sperm motility and the AR rate decreased significantly (p < 0.05) in Ca2+-free and low Ca2+ medium. The addition of 10 microM Ca2+ ionophore A23187 potently stimulated AR. After incubation for capacitation, the PKC activator phorbol 12-myristate 13-acetate (PMA) stimulated AR in a dose-dependent manner and its effect could be overcome by the PKC inhibitor staurosporine. These results suggest that Ca2+ and PKC play an important role in the sperm acrosome reaction of the giant panda.
Sun
Q Y
QY
State Key Laboratory of Reproductive Biology, Institute of Zoology, Academia Sinica, Beijing, 100080, PR China.
Liu
H
H
Li
X B
XB
Song
X F
XF
Yu
J Q
JQ
Li
G H
GH
Chen
D Y
DY