Evidence that potassium channels mediate the effects of serotonin on the ocular circadian pacemaker of Aplysia.
Evidence that potassium channels mediate the effects of serotonin on the ocular circadian pacemaker of Aplysia.
复制标题
有证据表明钾通道介导血清素对海兔眼昼夜节律起搏器的影响。
DOI：
10.1007/bf00194112
复制
发表时间：
1992
期刊：
影响因子：
--
通讯作者：
Block,GD
中科院分区：
文献类型：
--
作者：
Colwell,CS;Michel,S;Block,GD
The eye of the marine molluskAplysia californicacontains a photo-entrainable circadian pacemaker that drives an overt circadian rhythm of spontaneous compound action potentials in the optic nerve. Serotonin is known to influence the phase of this ocular rhythm. The aim of the present study was to evaluate whether potassium channels are involved in effects on the ocular circadian rhythm. Our experimental approach was to study the effect of the potassium channel antagonist barium on serotonin-induced phase shifts of this rhythm. The application of barium was found to block serotonininduced phase shifts whereas barium alone did not cause significant phase shifts. The effects of barium were found to be dose dependent. In addition, barium blocked forskolin-induced phase advances but did not interfere with serotonin-induced increases in cAMP content. Finally, barium antagonized serotonin-induced suppression of compound action potential activity. These results are consistent with a model in which the application of serotonin phase shifts the ocular pacemaker by causing a membrane hyperpolarization which is mediated by a cAMP-dependent potassium conductance.
