Marine Biology Laboratory, Earth and Life Institute, Catholic University of Louvain, Place Croix du Sud 3, Louvain-la-Neuve 1348, Belgium.
J Exp Biol. 2013 Nov 15;216(Pt 22):4285-9. doi: 10.1242/jeb.090852. Epub 2013 Aug 15.
Tomopteris helgolandica Greeff 1879 (Tomopteridae) is a transparent holoplanktonic polychaete that can emit a bright light. In this study, we investigated the emission pattern and control of this deep-sea worm's luminescence. Potassium chloride depolarisation applied on anaesthetised specimens triggered a maximal yellow light emission from specific parapodial sites, suggesting that a nervous control pathway was involved. Pharmacological screening revealed a sensitivity to carbachol, which was confirmed by a dose-light response associated with a change in the light emission pattern, where physiological carbachol concentrations induced flashes and higher concentrations induced glows. The light response induced by its hydrolysable agonist, acetylcholine, was significantly weaker but was facilitated by eserine pretreatment. In addition, a specific inhibitory effect of tubocurarine was observed on carbachol-induced emission. Lastly, KCl- and carbachol-induced light responses were significantly reduced when preparations were pre-incubated in Ca(2+)-free artificial seawater or in different calcium channel blockers (verapamil, diltiazem) and calmodulin inhibitor (trifluoperazine) solutions. All of these results strongly suggest that T. helgolandica produces its light flashes via activation of nicotinic cholinergic receptors and a calcium-dependent intracellular mechanism involving L-type calcium channels.
汤姆氏磷沙蚕（Tomopteris helgolandica）是一种透明的深海浮游多毛类动物，能够发出明亮的光。在这项研究中，我们研究了这种深海蠕虫发光的模式和控制机制。对麻醉标本施加氯化钾去极化会触发特定的副肢部位发出最大的黄色光，表明存在神经控制途径。药理学筛选显示对乙酰胆碱敏感，这一点通过与发光模式变化相关的剂量-光反应得到了证实，其中生理浓度的乙酰胆碱诱导闪光，而更高浓度则诱导辉光。其可水解激动剂乙酰胆碱诱导的光反应虽然较弱，但在 eserine 预处理后得到促进。此外，还观察到在 carbachol 诱导的发射中，tubocurarine 具有特异性抑制作用。最后，当在不含 Ca2+的人工海水中或不同的钙通道阻滞剂（维拉帕米、地尔硫卓）和钙调蛋白抑制剂（三氟拉嗪）溶液中预先孵育时，KCl 和 carbachol 诱导的发光反应显著降低。所有这些结果强烈表明，T. helgolandica 通过激活烟碱型胆碱能受体和涉及 L 型钙通道的钙离子依赖性细胞内机制产生其光闪烁。
