D-丝氨酸对N-甲基-D-天冬氨酸诱导大鼠海马cGMP释放作用的影响

Effect of D-serine on N-methyl-D-aspartateinduced efflux  of cGMP from rat hippocampus

Ｄ┐丝氨酸对Ｎ┐甲基┐Ｄ┐天冬氨酸诱导大鼠海马ｃＧＭＰ释放作用的影响金英刘晓娟王化洲（锦州医学院药理学教研室，锦州１２１００１）很久以来，人们一直认为高级脊椎动物几乎不产生也不利用Ｄ－氨基酸系列［１］．然而，最近越来越多的实验表明在成年哺乳动物包括人...

The microdialysis technique was utilized to study the effects of exogenous D-serine on the cGMP level in the perfusate of rat hippocampus. Addition of N-methyl-D-aspartate (NMDA) 250 μmol·L1 to the perfusate resulted in a striking increase of cGMP in perfusate. The cGMP response elicited by NMDA was prevented by 7-chlorokynurenic acid (7CKA), a selective antagonist at the glycine site of the NMDA receptor. Dserine completely reversed the antagonism by 7-CKA of the NMDAevoked cGMP response. The NMDAevoked cGMP response was enhanced by D-serine. D-serine alone was inactive. The data show that D-serine, administered to freelymoving rats, behaves as a selective agonist at the glycine site of hippocampus NMDA receptor. Furthermore, these results suggest that the glycine modulatory site may not be fully saturated in vivo, and thus can serve to regulate NMDA receptor function. 