TRIGGER MECHANISM OF ACROSOME REACTION IN HUMAN SPERM MEDIATED BY ADENOSINE RECEPTOR

体外洗精浆诱导自发顶体反应（AR），而腺苷的存在抑制了这种诱导。几种腺苷A1受体激动剂抑制了AR的诱导，而腺苷A1受体竞争拮抗剂FK-352、FK-838加速了AR的诱导。L型钙通道阻滞剂的存在使这种现象消失。腺苷A2受体激动剂和拮抗剂对ar无影响，精浆中腺苷浓度比血清高10倍以上。比较人精浆和血清中腺苷嘌呤的组成，前者中腺苷占60%以上，后者中腺苷嘌呤90%以上为ATP和ADP。腺苷A1受体与L型钙通道连接。提示精浆腺苷通过腺苷A1受体抑制AR的诱导。去除精浆（洗去腺苷）消除了抑制作用，允许钙离子流入顶体。

Removal of seminal plasma by washing induced spontaneous acrosome reaction (AR), in vitro, whereas presence of adenosine suppressed the induction. Several agonists against adenosine A1 receptor suppressed the induction of AR, and the competitive antagonists (FK-352, FK-838) against adenosine A1 receptor accellerated the induction of AR. There phenomena disappeared by the presence of L type calcium channel blocker. Agonists and antagosists against adenosine A2 receptor gave no influence for AR.Adenosine concentration in the seminal plasma was found to be more than 10 times higher than that of the serum. When compared the composition of adenyl purines in human seminal plasma and the serum, adenosine occupied more than 60% in the former, whereas more than 90% of adenyl purines were found to be ATP and ADP in the latter.Adenosine A1 receptor linked with L type calcium channel. There results suggested that the seminal plasma adenosine suppressed the induction of AR through adenosine A1 receptor. Removal of seminal plasma (wash out of adenosine) deleted the suppression, allowed to influx of calcium ion into the acrosome.