Freund-Mercier M J, Richard P
Brain Res. 1977 Jul 22;130(3):505-20. doi: 10.1016/0006-8993(77)90112-3.
Extracellular recording of paraventricular neurones after electrical stimulation of the neurohypophysis reveals three cell types: type I cells, invaded by an antidromic action potential; type II cells, whose evoked response is orthodromic; and type III cells, which do not respond to stimulation. During the oestrous cycle of the rat, type I cells are the only ones in the paraventricular nucleus (PVN) whose spontaneous activity (expressed in number of action potentials per second) varies. It is significantly higher during lactation (3.6 "/- 0.6) and pro-oestrus (3.4 "/- 0.5) than during oestrus (2.0 +/- 0.5), metoestrus (1.2 +/- 0.3) and dioestrus (1.5 +/- 0.4). There are significantly more phasic units during prooestrus. The mean spontaneous firing rate of type II and III cells, remain unchanged. The reflex activity of those neurones was studied. Vaginal dilatation, which evokes a release of oxytocin31, increases the activity of a small percentage of type I cells, but there are no differences in this response at different stages of the cycle and lactation. Silent and phasic type I units are never activated. Only the evoked activity of type III cells is affected by the endocrine state. These results are discussed in the light of the known or hypothetical roles of these different cells.
电刺激神经垂体后对室旁神经元进行细胞外记录，可发现三种细胞类型：I型细胞，可被逆向动作电位侵入；II型细胞，其诱发反应为顺向；III型细胞，对刺激无反应。在大鼠的发情周期中，I型细胞是室旁核（PVN）中唯一自发活动（以每秒动作电位数量表示）会发生变化的细胞。其在哺乳期（3.6±0.6）和发情前期（3.4±0.5）明显高于发情期（2.0±0.5）、间情期（1.2±0.3）和动情间期（1.5±0.4）。发情前期的相位单位明显更多。II型和III型细胞的平均自发放电率保持不变。对这些神经元的反射活动进行了研究。诱发催产素释放的阴道扩张会增加一小部分I型细胞的活性，但在发情周期和哺乳期的不同阶段，这种反应没有差异。沉默型和相位型I型单位从未被激活。只有III型细胞的诱发活动受内分泌状态影响。根据这些不同细胞已知或假设的作用对这些结果进行了讨论。
