Rotte C, Krach C, Balfanz S, Baumann A, Walz B, Blenau W
Institute of Biochemistry and Biology, Animal Physiology, University of Potsdam, Karl-Liebknecht-Str. 24-25, Haus 26, D-14476, Potsdam-Golm, Germany.
Neuroscience. 2009 Sep 15;162(4):1120-33. doi: 10.1016/j.neuroscience.2009.05.066. Epub 2009 May 29.
The phenolamines octopamine and tyramine control, regulate, and modulate many physiological and behavioral processes in invertebrates. Vertebrates possess only small amounts of both substances, and thus, octopamine and tyramine, together with other biogenic amines, are referred to as "trace amines." Biogenic amines evoke cellular responses by activating G-protein-coupled receptors. We have isolated a complementary DNA (cDNA) that encodes a biogenic amine receptor from the American cockroach Periplaneta americana, viz., Peatyr1, which shares high sequence similarity to members of the invertebrate tyramine-receptor family. The PeaTYR1 receptor was stably expressed in human embryonic kidney (HEK) 293 cells, and its ligand response has been examined. Receptor activation with tyramine reduces adenylyl cyclase activity in a dose-dependent manner (EC(50) approximately 350 nM). The inhibitory effect of tyramine is abolished by co-incubation with either yohimbine or chlorpromazine. Receptor expression has been investigated by reverse transcription polymerase chain reaction and immunocytochemistry. The mRNA is present in various tissues including brain, salivary glands, midgut, Malpighian tubules, and leg muscles. The effect of tyramine on salivary gland acinar cells has been investigated by intracellular recordings, which have revealed excitatory presynaptic actions of tyramine. This study marks the first comprehensive molecular, pharmacological, and functional characterization of a tyramine receptor in the cockroach.
酚胺类物质章鱼胺和酪胺控制、调节并影响无脊椎动物的许多生理和行为过程。脊椎动物体内这两种物质的含量很少，因此，章鱼胺和酪胺与其他生物胺一起被称为“痕量胺”。生物胺通过激活G蛋白偶联受体引发细胞反应。我们从美洲大蠊Periplaneta americana中分离出了一个编码生物胺受体的互补DNA（cDNA），即Peatyr1，它与无脊椎动物酪胺受体家族成员具有高度的序列相似性。PeaTYR1受体在人胚肾（HEK）293细胞中稳定表达，并对其配体反应进行了检测。酪胺激活受体可使腺苷酸环化酶活性呈剂量依赖性降低（半数有效浓度约为350 nM）。酪胺的抑制作用可通过与育亨宾或氯丙嗪共同孵育而消除。通过逆转录聚合酶链反应和免疫细胞化学研究了受体的表达情况。该mRNA存在于包括脑、唾液腺、中肠、马氏管和腿部肌肉在内的各种组织中。通过细胞内记录研究了酪胺对唾液腺腺泡细胞的影响，结果显示酪胺具有兴奋性突触前作用。这项研究标志着首次对蟑螂中的酪胺受体进行了全面的分子、药理学和功能特性分析。
