人工诱导贻贝Mytilus edulis Linnaeus幼虫附着变态的研究

许多天然物质和人为的外界生物化学因子对许多无脊椎动物附着变态有诱导作用，这为人工控制无脊椎动物幼虫的附着变态过程提供了重要手段，同时对于幼虫培养，特别是对于经济种类幼虫的培养和育苗，具有重要的意义。本文以青岛贻贝Mytilus edulis Linnaeus为研究对象，于1990年1991年分别就不同的海水离子条件、拟肾上腺素和抗肾上腺素、拟胆碱和抗胆碱类化合物以及促进生物新陈代谢类化合物对贻贝幼虫附着变态的诱导作用进行了研究，结果表明：升高K~+或Ca~++浓度以及降低Mg~++浓度均对贻贝幼虫有附着变态诱导作用。Mg~++浓度降低促进K~+的诱导作用。氨基酸类神经递质GABA和其同系物天冬氨酸、谷氨酸、苷氨酸、β－丙氨酸无明显附着变态诱导作用。短时间内，L－DOPA诱导水平（30％）贻贝幼虫不经过附着而直接变态，只作用于β－受体的拟肾上腺素、多巴胺和异丙肾上腺素诱导50％水平的幼虫变态。作用于α－受体的拟肾上腺素、间羟胺、麻黄碱、去氧肾上腺素、去甲肾上腺素和肾上腺素诱70－90％水平的幼虫变态。阻断β－受体的抗肾上腺素、噻吗心安和心得安无诱导作用。但阻断β－受体的抗肾上腺素、立其丁、酚苄明和妥拉苏林对幼虫附着变态有诱导作用。干扰肾上腺素能神经递质释放的化合物利血平无变态诱导作用，并有致死作用。拟胆碱类分合物苯海过、琥珀酰胆碱和阿托品对贻贝幼虫均有附着变态诱导作用。变态诱导率维持在30％水平。拟胆碱化合物加兰他敏有较高的变态诱导率（56.1% (10~(-3)M, 36h)）。抗胆碱类化合物氯丙嗪无明显诱导作用。调节生物体代谢和机能类化合物甲状腺素、ATP、肌、VitB_6和氨茶碱对贻贝幼虫有显著的附着变诱导作用，变态诱导率分别为：甲状腺素84.6 (10~(-3)M, 36h)；ATP 57.7% (10~(-3)M, 36h)；肌苷74.0% (10~(-3)M, 36h); VitB_6 41.3% (10~(-5)M, 36h)和氨茶碱50.0% (10~(-4)M, 36h)。前列腺素无诱导作用，而氯化可的松有一定诱导作用。去甲肾上腺素和乙酰胆碱对幼虫变态的诱导作用被Na~+通道阻断剂普鲁卡因和利多卡因阻断。但ATP和氨茶碱的诱导作用不被其阻断。这表明去甲肾上腺素和乙酰胆碱对幼虫的附着变态的诱导作用是通过视经传递完成的。而神经传递并没有参与ATP和氨茶碱对幼虫变态的诱导过程。

化学物质对海湾扇贝幼虫变态诱导作用的研究

本文试验了儿茶酚胺类，氨基酸类和金属离子类物质对海湾扇贝幼虫变态的诱导作用，研究结果显示，10~(-4)－10~(-6)M的肾上腺素，10~(-5)M的去甲肾上腺素和L－DOPA具有十分显著的诱导能力；GABA、赖氨酸和酪氨酸表现出一定的诱导作用；外加浓度的KCl和CaCl_2处理幼虫一定时间后，对其变态有比较显著的促进作用。肾上腺素、L－DOPA和KCl以不同时间处理幼虫，幼虫对肾上腺素和L－DOPA表现出很高的敏感性，而KCl对幼虫的诱导则表现出对时间和剂量较强的依赖性。这就显示肾上腺素和L－DOPA可能作用于幼虫体内的特异性受体，从而启动了幼虫的变态过程；而外加的K~+影响了细胞的膜电位，引起敏感细胞的去极化，转而促进了幼虫的变态。本实验的结果可以应用经济贝类贝类苗中生产中幼虫变态的诱导，对海洋生物幼虫生物学的研究亦具有一定的价值。

Simultaneous determination of monoamine and amino acid neurotransmitters in rat endbrain tissues by pre-column derivatization with high-performance liquid chromatographic fluorescence detection and mass spectrometric identification

A sensitive and efficient method for simultaneous determination of glutamic acid (Glu), gamma-amino-butyric acid (GABA), dopamine (DA), 5-hydroxytryptamine (5-HT) and 5-hydroxyindole acetic acid (5-HIAA) in rat endbrains was developed by high-performance liquid chromatography (HPLC) with fluorescence detection and on-line mass spectrometric identification following derivatization with 1,2-benzo-3,4-dihydrocarbazole-9-ethyl chloroformate (BCEOC). Different parameters which influenced derivatization and separation were optimized. The complete separation of five neurotransmitter (NT) derivatives was performed on a reversed-phase Hypersil BDS-C-18 column with a gradient elution. The rapid structure identification of five neurotransmitter derivatives was carried out by on-line mass spectrometry with electrospray ionization (ESI) source in positive ion mode, and the BCEOC-labeled derivatives were characterized by easy-to-interpret mass spectra. Stability of derivatives, repeatability, precision and accuracy were evaluated and the results were excellent for efficient HPLC analysis. The quantitative linear range of five neurotransmitters were 2.441-2 x 10(4) nM, and limits of detection were in the range of 0.398-1.258 nM (S/N = 3:1). The changes of their concentrations in endbrains of three rat groups were also studied using this HPLC fluorescence detection method. The results indicated that exhausting exercise could obviously influence the concentrations of neurotransmitters in rat endbrains. The established method exhibited excellent validity, high sensitivity and convenience, and provided a new technique for simultaneous analysis of monoamine and amino acid neurotransmitters in rat brain. (C) 2008 Elsevier B.V. All rights reserved.