Goldfish hypothalamic neuroendocrine cells have been investigated with intracellular recordings. The cells showed resting potentials of 50 mv and action potentials up to 117 mv followed by a long lasting and prominent diphasic hyperpolarizing afterpotential. The action potential occurred in two steps indicating sequential invasion. "Total" neuron (input) resistance was measured to be 3.3 x 107 Ω and total neuron time constant was 42 msec. Orthodromic volleys, produced by olfactory tract stimulation, generated graded excitatory postsynaptic potentials. These neuroendocrine cells seem, therefore, to have electrical membrane properties that are similar to those of other central neurons. Antidromic volleys (pituitary stimulation) produced inhibitory post-synaptic potentials whose latency was only slightly longer than that of the antidromic spike indicating the presence of recurrent collaterals. This finding suggests that the concept of the neuroendocrine cell as a neuron whose axon forms contacts only on blood vessels and not on other neurons or effector cells is too restrictive. Perfusion of the gills with dilute (0.3 per cent) sea water produced an inhibition of spontaneous activity. This inhibition is discussed in relation to recent work which demonstrates that goldfish hypothalamic hormones facilitate Na+ influx across the gill membrane.
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机译：金鱼下丘脑神经内分泌细胞已通过细胞内记录进行了研究。细胞显示出50 mv的静息电位和高达117 mv的动作电位，随后呈现持久且突出的双相超极化后电位。动作电位分两步出现，表明有序侵袭。测量的“总”神经元（输入）电阻为3.3 x 107Ω，总神经元时间常数为42毫秒。嗅觉刺激产生的正射性凌空产生分级的兴奋性突触后电位。因此，这些神经内分泌细胞似乎具有与其他中枢神经元相似的电膜特性。抗病性截击（垂体刺激）产生抑制性的突触后电位，其潜伏期仅比抗病性峰值的潜伏期稍长，表明存在反复的侧支。这一发现表明，神经内分泌细胞是一种神经元，其轴突仅与血管接触，而不与其他神经元或效应细胞接触，这一概念过于严格。用稀海水（0.3％）灌注the，会抑制自发活动。结合最近的工作讨论了这种抑制作用，该工作表明金鱼的下丘脑激素可促进Na +穿过membrane膜流入。
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