Bradwejn J, de Montigny C
Nature. 1984;312(5992):363-4. doi: 10.1038/312363a0.
Cholecystokinin (CCK) is a neuropeptide present in the mammalian central nervous system (CNS). In all species studied so far, the highest concentrations of this neuropeptide have been found in the cerebral cortex, the amygdala and the hippocampus. Five molecular forms of CCK having 39, 33, 13, 8 and 4 amino acid residues have been identified in the CNS, the sulphated octapeptide (CCK8) being the most abundant form detected. Specific CCK binding sites have been demonstrated in the rat, guinea pig and human brain. CCK8, applied by microiontophoresis to deep cortical neurones and hippocampal pyramidal neurones, has a powerful excitatory effect, whereas the non-sulphated CCK octapeptide has no such effect on these neurones. Low doses of benzodiazepines depress the spontaneous activity of hippocampal pyramidal neurones. We report here that benzodiazepines at very low doses antagonize selectively the CCK8-induced activation of rat hippocampal pyramidal neurones. This antagonistic action might be involved in the anxiolytic effect of these drugs.
胆囊收缩素（CCK）是一种存在于哺乳动物中枢神经系统（CNS）中的神经肽。在迄今研究的所有物种中，已发现这种神经肽在大脑皮层、杏仁核和海马体中的浓度最高。在中枢神经系统中已鉴定出具有39、33、13、8和4个氨基酸残基的五种CCK分子形式，其中硫酸化八肽（CCK8）是检测到的最丰富的形式。在大鼠、豚鼠和人类大脑中已证实存在特异性CCK结合位点。通过微离子电泳施加到深层皮质神经元和海马锥体神经元上的CCK8具有强大的兴奋作用，而非硫酸化的CCK八肽对这些神经元没有这种作用。低剂量的苯二氮䓬类药物可抑制海马锥体神经元的自发活动。我们在此报告，极低剂量的苯二氮䓬类药物可选择性拮抗CCK8诱导的大鼠海马锥体神经元的激活。这种拮抗作用可能与这些药物的抗焦虑作用有关。
