Thiéry J C, Pelletier J
Neuroendocrinology. 1981 Apr;32(4):217-24. doi: 10.1159/000123162.
Changes in multiunit activity (MUA) in the anterior median eminence and adjacent tissues just posterior to the optic chiasma were recorded in lightly anaesthetized, ovariectomized ewes after an i.m. injection either of oil (group I) or of 50 microgram oestradiol benzoate (ODB) in oil (group II). Changes in plasma LH concentration that occurred during the recording were determined by radioimmunoassay. In both groups, when the electrodes reached the correct site, the MUA showed a bursting pattern of firing with a frequency of 0.5-1.5 bursts/s. In group I (10 ewes), the MUA showed circhoral variations at intervals of 55.1 +/- 2.8 min similar to those for LH pulses. Plasma LH levels, measured every 10 min, for 2 h in 8 ewes, showed a total of 14 pulses which were always preceded by an increase in MUA. Hormonal values and bioelectrical activity were positively correlated (p < 0.01). When cumulated hourly, the mean MUA in group I remained stable, from 10.5 to 22.5 h after oil treatment. Then, intravenous injection of 100 microgram of ODB induced a rapid increase in MUA. During the 2 h after this injection, we observed only two pulses of LH in the 8 studied ewes. In animals injected i.m. with ODB before the recording (group II, n = 16), the mean MUA (cumulated every hour) from 10.5 to 22.5 postinjection was significantly higher (p < 0.001) than in animals from group I (control). Within group II, 5 ewes discharged an obvious peak of LH, 18-24 h after ODB injection and showed a shortening of the MUA circhoral period (which varied from 10 to 20 min, at the time of initiation of the surge) followed by an increase in the mean amplitude. These 5 ewes showed a significantly higher increase (p < 0.03) in the MUA per hour (from 10.5 to 22.5 h after ODB) than the 9 which did not show an LH peak. Thus, the changes in MUA were clearly related in time to changes in LH secretion whether occurring as spontaneous pulses or as peaks induced by ODB.
对轻度麻醉的去卵巢母羊进行肌内注射，一组注射油剂（I组），另一组注射溶于油剂的50微克苯甲酸雌二醇（ODB）（II组），记录视交叉前方正中隆起及视交叉后方相邻组织的多单位活动（MUA）变化。记录期间血浆促黄体生成素（LH）浓度的变化通过放射免疫测定法测定。在两组中，当电极到达正确位置时，MUA呈现出爆发式放电模式，频率为0.5 - 1.5次爆发/秒。在I组（10只母羊）中，MUA呈现出间隔为55.1±2.8分钟的昼夜节律变化，类似于LH脉冲的变化。在8只母羊中，每10分钟测量一次血浆LH水平，持续2小时，共出现14个脉冲，且每个脉冲之前MUA都会增加。激素值与生物电活动呈正相关（p<0.01）。I组每小时累积的平均MUA在油剂处理后10.5至22.5小时保持稳定。然后，静脉注射100微克ODB导致MUA迅速增加。在此注射后的2小时内，在8只受试母羊中仅观察到2个LH脉冲。在记录前肌内注射ODB的动物（II组，n = 16）中，注射后10.5至22.5小时每小时累积的平均MUA显著高于I组（对照组）动物（p<0.001）。在II组中，5只母羊在ODB注射后18 - 24小时出现明显的LH峰值，MUA昼夜周期缩短（在LH峰开始时从10至20分钟不等），随后平均幅度增加。这5只母羊每小时MUA的增加幅度（ODB注射后10.5至22.5小时）显著高于未出现LH峰值的9只母羊（p<0.03）。因此，无论是自发脉冲还是ODB诱导的峰值，MUA的变化在时间上都与LH分泌的变化明显相关。
