Herberg L J, De Belleroche J S, Rose I C, Montgomery A M
Experimental Psychology Laboratory, Institute of Neurology, London, UK.
Neurosci Lett. 1992 Jun 8;140(1):16-8. doi: 10.1016/0304-3940(92)90671-s.
It is unclear whether behavioral depression and suppression of food intake by cholecystokinin (CCK) is contributed to by aversive gastrointestinal effects such as nausea. In the present study we examined the effect of a new antiemetic agent, ondansetron, a specific antagonist of 5-HT3 receptors, on suppression of variable-interval self-stimulation by the CCK analogue caerulein. Responding by rats for brain-stimulation reward is especially sensitive to CCK, and provides a convenient means of investigating this question. Caerulein (30 micrograms/kg, s.c.), injected alone, was followed by a profound (ca. 80%) reduction in the rate of self-stimulation, lasting about 30 min. Ondansetron (1.0-1000 micrograms/kg, s.c.) injected on its own had no effect on self-stimulation rate, and a 100-micrograms/kg dose did not lessen the depressant action of caerulein. The behavioural depressant effects of CCK are thus unlikely to depend on brain mechanisms for nausea and vomiting involving 5-HT3 receptors.
尚不清楚行为性抑郁以及胆囊收缩素（CCK）对食物摄入的抑制作用是否由诸如恶心等厌恶性胃肠道效应所致。在本研究中，我们检测了一种新型止吐药昂丹司琼（一种5-HT3受体特异性拮抗剂）对CCK类似物蛙皮素抑制可变间隔自我刺激的影响。大鼠对脑刺激奖赏的反应对CCK尤为敏感，这为研究该问题提供了一种便捷的方法。单独注射蛙皮素（30微克/千克，皮下注射）后，自我刺激率显著降低（约80%），持续约30分钟。单独注射昂丹司琼（1.0 - 1000微克/千克，皮下注射）对自我刺激率没有影响，100微克/千克的剂量也没有减轻蛙皮素的抑制作用。因此，CCK的行为抑制作用不太可能依赖于涉及5-HT3受体的恶心和呕吐的脑机制。
