Athey G R, Cooke A R, Wood J D
Am J Physiol. 1981 Jun;240(6):G437-41. doi: 10.1152/ajpgi.1981.240.6.G437.
To study further the ongoing spike discharge of burst-type myenteric neurons, extracellular recordings were made with either Teflon-insulated Pt wire electrodes (tip diam, 20 micrometers) or 3 M NaCl-filled glass micropipettes (tip diam, 1-2 micrometers). Presynaptic fibers to the erratic bursters were activated by electrical shocks delivered through Teflon-insulated Pt wire electrodes. Single electrical shocks applied to either the surface of the ganglion or an interganglionic connective elicited bursts of spikes that had parameters (interspike intervals and spikes per burst) that closely resembled the spontaneously occurring bursts in the same neuron. The latencies of the responses to electrical stimulation ranged from 5 to 30 ms. The responses were reversibly abolished when the concentration of Mg2+ in the bathing solution was elevated to 12 mM. The responses to electrical stimulation were unaffected by atropine, hexamethonium, d-tubocurarine, epinephrine, norepinephrine, methysergide, morphine, naloxone, and substance P. The ongoing burst-type discharge of cat myenteric neurons appeared to reflect a synaptic event that could be mimicked by electrical stimulation of presynaptic fibers. The identity of the neurotransmitter that elicits the burst-type discharge is unknown. The transmitter is probably not acetylcholine, serotonin, norepinephrine, an opiatelike peptide, nor substance P.
为了进一步研究爆发型肌间神经元持续的锋电位发放，采用聚四氟乙烯绝缘的铂丝电极（尖端直径20微米）或充满3M氯化钠的玻璃微电极（尖端直径1 - 2微米）进行细胞外记录。通过聚四氟乙烯绝缘的铂丝电极施加电刺激来激活向不规则爆发神经元投射的突触前纤维。对神经节表面或神经节间结缔组织施加单次电刺激可引发锋电位爆发，其参数（峰峰间期和每次爆发的峰电位数量）与同一神经元自发出现的爆发非常相似。对电刺激的反应潜伏期为5至30毫秒。当浴液中镁离子浓度升高至12毫摩尔时，反应可逆性消失。电刺激反应不受阿托品、六甲铵、d - 筒箭毒碱、肾上腺素、去甲肾上腺素、麦角新碱、吗啡、纳洛酮和P物质的影响。猫肌间神经元持续的爆发型放电似乎反映了一种可通过突触前纤维电刺激模拟的突触事件。引发爆发型放电的神经递质身份尚不清楚。该递质可能不是乙酰胆碱、5 - 羟色胺、去甲肾上腺素、阿片样肽，也不是P物质。
