Paisley A C, Summerlee A J
J Physiol. 1984 Feb;347:465-78. doi: 10.1113/jphysiol.1984.sp015076.
Extracellular electrical recordings were taken from twenty antidromically identified paraventricular neurones in unanaesthetized, unrestrained rabbits. Neuronal activity was correlated with nursing behaviour of the doe and responses of the young during suckling. Magnocellular neurones were divided into two groups on the basis of their activity in suckling. Group 1 (n = 14) showed several discrete bursts of high-frequency activity whilst neurones in group 2 (n = 6) did not. Neurones in group 1 showed 5-9 bursts of high-frequency activity in suckling. Each burst lasted 1-4 s and represented a 3-10-fold rise in the discharge of the cell. These units were classified as oxytocinergic, as their stereotyped activation preceded bouts of sucking behaviour of the young indicative of milk ejection. All fourteen cells continued to show intermittent bursts of neurosecretory activity for up to 20 min after nursing terminated. This pattern of discharge followed grooming behaviour of the doe. In contrast, neurones in group 2 (n = 6) showed no high-frequency activity in suckling. They showed a significant fall in their discharge frequency compared with pre-suckling values (P less than 0.05; Student's t test) and a significant (P less than 0.05) lengthening of the modal interspike interval. They were classed as potential vasopressin-producing cells. Control recordings were taken from thirty-two neurones which could not be antidromically driven. The recording sites were shown histologically to be in the lateral hypothalamic area. These cells showed a significant fall in their discharge frequency (P less than 0.05) and a significant increase (P less than 0.01) in the modal interval during suckling. Cross-correlation studies of the activity, recorded from one electrode, of groups of neurones clustered around a single hypothalamic neurone suggest that bursting discharge from the putative oxytocin neurones in suckling is accompanied by the synchronous activation of some of the surrounding magnocellular units.
在未麻醉、未束缚的家兔中，对20个经逆向鉴定的室旁核神经元进行了细胞外电记录。神经元活动与母兔的哺乳行为以及幼兔在哺乳期间的反应相关。根据其在哺乳期间的活动，将大细胞神经元分为两组。第1组（n = 14）显示出几次离散的高频活动爆发，而第2组（n = 6）的神经元则没有。第1组的神经元在哺乳期间显示出5 - 9次高频活动爆发。每次爆发持续1 - 4秒，代表细胞放电增加3 - 10倍。这些单元被归类为催产素能神经元，因为它们刻板的激活先于幼兔的吸吮行为发作，这表明有乳汁排出。在哺乳结束后，所有14个细胞继续显示间歇性的神经分泌活动爆发，持续长达20分钟。这种放电模式跟随母兔的梳理行为。相比之下，第2组（n = 6）的神经元在哺乳期间没有高频活动。与哺乳前的值相比，它们的放电频率显著下降（P < 0.05；学生t检验），并且模式峰峰间期显著延长（P < 0.05）。它们被归类为潜在的产生血管加压素的细胞。对32个无法被逆向驱动的神经元进行了对照记录。组织学显示记录部位位于下丘脑外侧区。这些细胞在哺乳期间放电频率显著下降（P < 0.05），模式间期显著增加（P < 0.01）。对围绕单个下丘脑神经元聚集的神经元群从一个电极记录的活动进行互相关研究表明，哺乳期间假定的催产素神经元的爆发性放电伴随着一些周围大细胞单元的同步激活。
