乙酰胆碱和血清素对水蛭机械感受器敏感性的神经调节作用。

Neuromodulatory effects of acetylcholine and serotonin on the sensitivity of leech mechanoreceptors.

Gascoigne L, McVean A

Department of Biology, University of London, Egham, Surrey, U.K.

Comp Biochem Physiol C Comp Pharmacol Toxicol. 1991;99(3):369-74. doi: 10.1016/0742-8413(91)90258-u.

Abstract

Each segmental ganglion of the leech Hirudo medicinalis contains 6 touch (T) cells, 4 pressure (P) cells and 4 nociceptive (N) cells. The receptive terminals of these cells innervate the skin in discrete areas. These cells are known to have extrasynaptic receptors. 2. We tested the effect of transmitter substances present in leech CNS on the sensitivity of T and P cells to mechanical stimuli. Substances tested included octopamine, FMRFamide, proctolin, substance P, glutamate, GABA, acetylcholine and serotonin. 3. Only acetylcholine and serotonin had consistent effects. Serotonin (1 x 10(-3) M) increased the number of action potentials of T cells elicited by a standard stimulus. Serotonin (1 x 10(-4) M) and acetylcholine (1 x 10(-3) M) increased the number and frequency of action potentials in P cells.

摘要

医用水蛭（Hirudo medicinalis）的每个节段神经节包含6个触觉（T）细胞、4个压力（P）细胞和4个伤害性感受（N）细胞。这些细胞的感受性终末支配皮肤的离散区域。已知这些细胞具有突触外受体。2. 我们测试了水蛭中枢神经系统中存在的递质物质对T细胞和P细胞对机械刺激敏感性的影响。所测试的物质包括章鱼胺、FMRF酰胺、促肠肌肽、P物质、谷氨酸、γ-氨基丁酸、乙酰胆碱和5-羟色胺。3. 只有乙酰胆碱和5-羟色胺有一致的作用。5-羟色胺（1×10⁻³ M）增加了标准刺激引发的T细胞动作电位的数量。5-羟色胺（1×10⁻⁴ M）和乙酰胆碱（1×10⁻³ M）增加了P细胞动作电位的数量和频率。