The actions of a charged melatonin receptor ligand, TMEPI, and an irreversible MT2 receptor agonist, BMNEP, on mouse hippocampal evoked potentials in vitro.
The actions of a charged melatonin receptor ligand, TMEPI, and an irreversible MT2 receptor agonist, BMNEP, on mouse hippocampal evoked potentials in vitro.
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DOI：
10.1016/j.lfs.2004.06.009
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发表时间：
2004-11
期刊：
影响因子：
6.1
通讯作者：
Y. El-Sherif;P. Witt‐Enderby;Pui-Kai Li;Jene Tesoriero;M. V. Hogan;A. Wieraszko
中科院分区：
文献类型：
--
作者：
Y. El-Sherif;P. Witt‐Enderby;Pui-Kai Li;Jene Tesoriero;M. V. Hogan;A. Wieraszko
我们以前已经确定，褪黑激素调制海马突触传递的双相方式：一个初始的抑郁症，其次是恢复/放大阶段。在这里，我们描述了两个新的褪黑激素受体配体，BMNEP（N-溴乙酰基-2-碘-5-甲氧基色胺）和TMPEI（N-[2-（2-Trimethylammoniummethyleneoxy-7-methoxy）ethyl]propionamide碘化物），对群体峰电位（PS）和兴奋性突触后电位（EPSP）记录从小鼠海马脑片的影响。BMNEP特异性地烷基化并组成性地激活MT 2褪黑激素受体，通过不可逆地抑制PS和EPSP来模拟褪黑激素作用的第一阶段。TMPEI，质膜褪黑激素受体的带电配体，放大这些电位的方式类似于褪黑激素的效果，在第二个恢复阶段。褪黑激素对TMPEI作用所放大的电位无影响。我们的研究结果表明，褪黑激素及其类似物的双相，受体依赖性的行动调节海马谷氨酸能突触的效率，最有可能是通过两种不同的，顺序发生的机制介导。
We have previously determined that melatonin modulates hippocampal synaptic transmission in a biphasic way: an initial depression was followed by a recovery/amplification phase. Here we describe the influence of two novel melatonin receptor ligands, BMNEP (N-bromoacetyl-2-iodo-5-methoxytryptamine) and TMPEI (N-[2-(2-Trimethylammoniumethyleneoxy-7-methoxy)ethyl]propionamide iodide), on the population spike (PS) and excitatory postsynaptic potentials (EPSP) recorded from mouse hippocampal slices. BMNEP, which specifically alkylates and constitutively activates the MT2 melatonin receptor, mimicked the first phase of melatonin's action by irreversibly depressing both the PS and EPSP. TMPEI, a charged ligand of plasma membrane melatonin receptors, amplified those potentials in a manner similar to the effect of melatonin observed during the second, recovery phase. Melatonin had no influence on the potentials amplified by the action of TMPEI. Our results suggest that the biphasic, receptor-dependent action of melatonin and its analogs modulates the efficiency of the hippocampal glutamergic synapse and is most likely mediated through two different, sequentially occurring mechanisms.