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褪黑激素（ＭＥＬ）是松果体和视网膜分泌的一种重要内分泌激素，它参与生物季节周期昼夜节律，视网膜信号调制及其他多种重要生理功能的调节。关于鸟类视网膜中ＭＥＬ受体的定位和亲和性类型的研究已有报道，然而由于所用方法的限制，对它的电生理特性知之甚少。我们首次成功地在爪蟾卵母细胞上表达了鸡视网膜ＭＥＬ受体，并利用双电极电压箝技术及常用的药物灌流的方法研究了它的部分电生理、药理学特性。我们发现，这种表达的ＭＥＬ受体是高度敏感的，１ｐｍｏｌ／Ｌ的ＭＥＬ即可诱导出一个振荡型的内向电流，该电流很难失敏，反转电位接近－２６ｍＶ，可被高浓度的氯通道阻断剂９－ＡＣ明显抑制，亦可被钙离子螯合剂如ＢＡＰＴＡ－ＡＭ阻断。这些证据提示，这种表达的ＭＥＬ受体是通过激活钙依赖的氯离子通道而起作用。由于该电流不受咖啡因的影响，与目前已表达出的哺乳动物及鸡脑的ＭＥＬ受体有明显的差异。此外，该电流还可受到锌离子的调制。这些工作为今后研究的深入创造了良好条件。
Melatonin (MEL) is an important endocrine hormone secreted by the pineal gland and the retina. It is involved in the regulation of the circadian rhythms of the biological seasons, the modulation of retinal signaling and many other important physiological functions. Research on the type and localization of MEL receptors in the avian retina has been reported, however little is known about its electrophysiological properties due to the limitations of the methods used. For the first time, we successfully expressed chicken retinal MEL receptors on Xenopus oocytes, and studied its electrophysiological and pharmacological properties using bipolar voltage clamp technique and commonly used drug perfusion method. We found that this expressed MEL receptor is highly sensitive and 1 pmol / L of MEL induced an oscillatory inward current that was less susceptible to desensitization with a reversal potential near -26 mV, which could be induced by high concentrations of Chloride channel blocker 9-AC significantly inhibited, but also by calcium ion chelator such as BAPTA-AM block. These evidence suggest that this expressed MEL receptor functions by activating the calcium-dependent chloride channel. Since this current is unaffected by caffeine, there is a clear difference from the MEL receptors presently expressed in mammalian and chicken brain. In addition, the current can also be modulated by zinc ions. These works have created good conditions for further research.