Depoortere R, Di Scala G, Angst M J, Sandner G
D.N.B.C. Centre de Neurochimie du C.N.R.S., Strasbourg, France.
Pharmacol Biochem Behav. 1990 Oct;37(2):311-6. doi: 10.1016/0091-3057(90)90340-n.
Rats were trained to switch-off aversive electrical brain stimulations applied to the periaqueductal gray (PAG) or mesencephalic locomotor region (MLR) by pressing a bar (switch-off behavior). We investigated the effects of IP injections of the benzodiazepine (BZ) receptor inverse agonist FG 7142 (2.5, 5, 10 mg/kg) or BZ receptor agonist chlordiazepoxide (CDP: 5 mg/kg) on the switch-off latency, i.e., the time elapsed between the onset of the stimulation and its offset by a press of the bar. It was found that FG 7142 decreased, whereas CDP increased the mean switch-off latency for electrical stimulation of the PAG, which is interpreted as a potentiating effect of FG 7142 and a reducing effect of CDP on the electrically induced aversive state. By contrast, neither FG 7142 nor CDP were found to affect the mean switch-off latency for MLR stimulations. These results suggest a difference in the pharmacological sensitivity to BZ receptor ligands between aversive states elicited by electrical stimulation of the PAG or MLR.
训练大鼠通过按压杠杆来关闭施加于中脑导水管周围灰质（PAG）或中脑运动区（MLR）的厌恶性脑电刺激（关闭行为）。我们研究了腹腔注射苯二氮䓬（BZ）受体反向激动剂FG 7142（2.5、5、10毫克/千克）或BZ受体激动剂氯氮卓（CDP：5毫克/千克）对关闭潜伏期的影响，即刺激开始到通过按压杠杆使其停止之间所经过的时间。结果发现，FG 7142缩短了潜伏期，而CDP延长了对PAG进行电刺激时的平均关闭潜伏期，这被解释为FG 7142的增强作用和CDP对电诱导厌恶性状态的减弱作用。相比之下，未发现FG 7142和CDP对MLR刺激的平均关闭潜伏期有影响。这些结果表明，电刺激PAG或MLR所引发的厌恶性状态对BZ受体配体的药理敏感性存在差异。
