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

在体外，通过洗涤去除精浆可引起自发性顶体反应(AR)，而腺苷的存在则抑制这种诱导。腺苷A1受体激动剂抑制AR的诱导，而腺苷A1受体的竞争性拮抗剂(FK-352、FK-838)则促进AR的诱导。加入L钙通道阻滞剂后，上述现象消失。腺苷A2受体激动剂和拮抗剂不影响精浆中的腺苷浓度，精浆中的腺苷浓度是血清中的10倍以上。比较人精浆和血清中腺嘌呤的组成，前者腺苷占60%以上，后者腺苷占90%以上，腺苷A1受体与L型钙通道相连。结果提示，精浆中的腺苷通过腺苷A1受体抑制AR的诱导。去除精浆(洗掉腺苷)可以消除这种抑制作用，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.