Open AccessProgesterone‐enhanced sperm hyperactivation through IP 3 –PKC and PKA signals
Author(s) -
Fujinoki Masakatsu
Publication year - 2013
Publication title -
reproductive medicine and biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.005
H-Index - 22
eISSN - 1447-0578
pISSN - 1445-5781
DOI - 10.1007/s12522-012-0137-6
Subject(s) - hyperactivation , protein kinase c , phospholipase c , protein kinase a , adenylate kinase , inositol , chemistry , diacylglycerol kinase , inositol phosphate , endocrinology , signal transduction , medicine , second messenger system , cyclic adenosine monophosphate , capacitation , microbiology and biotechnology , kinase , biology , receptor , biochemistry , in vitro
Propose The present study examined whether regulation of progesterone‐enhanced hyperactivation of spermatozoa is associated with the production of inositol 1,4,5‐trisphosphate (IP 3 ) and diacylglycerol (DAG) by phospholipase C (PLC) and cyclic adenosine monophosphate (cAMP) by adenylate cyclase (AC), as well as activation of protein kinase C (PKC) and protein kinase A (PKA). Methods Hamster spermatozoa were hyperactivated by incubation for 4 h in modified Tyrode's albumin lactate pyruvate (mTALP) medium. In order to examine the effects of IP 3 receptor (IP 3 R), PKC and PKA on progesterone‐enhanced hyperactivation, their inhibitors (xestospongin C, bisindolylmaleimide 1 and H‐89) were used. Results Progesterone‐enhanced hyperactivation was significantly suppressed by the inhibitors of IP 3 R, PKC and PKA. Conclusions The results suggest that progesterone‐enhanced sperm hyperactivation occurs through two signal pathways. One is an intracellular Ca 2+ signal through production of IP 3 and DAG by PLC, binding of IP 3 to IP 3 R and activation of PKC by DAG and Ca 2+ . The other is a cAMP–PKA signal through production of cAMP by AC and activation of PKA by cAMP.