Alfadly Saeed Obeid, Batarfi Ali Mohamed, Veetil Praveen Kottath
Indian J Physiol Pharmacol. 2014 Jul-Sep;58(3):240-50.
The effects of Catha edulis, a CNS stimulant, on humans and animals have been studied on various aspects like anorectic effect, self-administration, stereotyped behavior, aggressive behavior, operant task, locomotor sensitization, psychosis etc., but how C. edulis influence spatial learning and memory in rats is not clear. C. edulis contains amphetamine like substances, which enhances spatial learning and memory. So, we hypothesize C. edulis will also influence spatial learning and memory. In the aim to assess this effect of C.edulis, a comparative study is conceded using another CNS stimulant, methylphenidate (MPD), which is currently used, for treatment of attention deficit hyperactive disorder (ADHD), instead of amphetamine. Spatial learning and memory was assessed using radial arm maze, by analyzing five dependent measures obtained on every trial: time to complete a trial, latency to first arm entry, number of reference memory errors, number of working memory correct and incorrect errors. Our results show that C. edulis and not MPD fed rats had impaired learning and memory, implicated by increased time to complete a trial. But both C. edulis and MPD increased attention in rats, as in both groups latency to first arm entry was less. Further analysis showed that C. edulis fed rats were more effected in the working memory component and reference memory was intact. These results highlight the importance of restricting the widespread use of C. edulis in humans. The use of MPD as a choice of drug in treatment of ADHD is also supported by this study as it did not deteriorate the learning and memory, in spite of increased attention and alertness. These results are further discussed on the basis of differential action of C. edulis and MPD on neurotransmitter systems of brain, and this reveals the need for detailed analysis in future studies for the effect of C. edulis on hippocampal network.
恰特草是一种中枢神经系统兴奋剂，人们已从多个方面对其对人和动物的影响进行了研究，如厌食作用、自我给药、刻板行为、攻击行为、操作性任务、运动致敏、精神病等，但恰特草如何影响大鼠的空间学习和记忆尚不清楚。恰特草含有类似苯丙胺的物质，可增强空间学习和记忆能力。因此，我们推测恰特草也会影响空间学习和记忆。为了评估恰特草的这种作用，我们进行了一项比较研究，使用另一种目前用于治疗注意力缺陷多动障碍（ADHD）的中枢神经系统兴奋剂哌甲酯（MPD）来替代苯丙胺。通过分析每次试验获得的五个相关指标，利用放射状臂迷宫评估空间学习和记忆能力：完成一次试验的时间、首次进入臂的潜伏期、参考记忆错误数量、工作记忆正确和错误的数量。我们的结果表明，喂食恰特草而非MPD的大鼠学习和记忆受损，这表现为完成一次试验的时间增加。但恰特草和MPD均提高了大鼠的注意力，因为两组首次进入臂的潜伏期都较短。进一步分析表明，喂食恰特草的大鼠在工作记忆部分受影响更大，而参考记忆则保持完整。这些结果凸显了限制恰特草在人类中广泛使用的重要性。本研究还支持将MPD作为治疗ADHD的药物选择，因为尽管它提高了注意力和警觉性，但并未损害学习和记忆。基于恰特草和MPD对大脑神经递质系统的不同作用，对这些结果进行了进一步讨论，这表明未来研究需要对恰特草对海马网络的影响进行详细分析。
