Broersen L M, Heinsbroek R P, de Bruin J P, Uylings H B, Olivier B
Graduate School Neurosciences Amsterdam, Netherlands Institute for Brain Research.
Brain Res. 1995 Mar 20;674(2):221-9. doi: 10.1016/0006-8993(95)00025-l.
The putative involvement of the dopaminergic innervation of the medial part of the prefrontal cortex (PFC) in short-term memory functioning was investigated by evaluating the effects of local infusions of dopaminergic drugs into the ventral part of the medial PFC of rats in an operant delayed-matching-to-position (DMTP) task. Two separate groups of rats were tested after bilateral microinfusion of several doses of either the dopamine receptor agonist apomorphine (APO) or the dopamine receptor antagonist cis-flupenthixol (FLU) into the ventromedial PFC. In addition, all animals were tested after infusion of several doses of the muscarinic receptor antagonist scopolamine (SCO) and the dopamine DI receptor antagonist SCH-23390 (SCH). The drugs tested affected DMTP performance differentially. APO had no effect on response accuracy, although it dose-dependently affected nose poke activity and response latencies. FLU and SCH both induced a dose-dependent, but delay-independent deterioration of response accuracy that was paralleled by increases in response latencies and decreases in nose poke frequencies, causing some animals to stop responding after infusion of the highest doses of both drugs. In contrast, SCO infusions into the ventromedial PFC induced a dose- and delay-dependent deterioration of response accuracy, that was accompanied by an increase in response latencies only. Taken together, these results provide additional support for the involvement of cholinergic, rather than dopaminergic mechanisms in short-term memory supported by the medial PFC of the rat, and they are not in favor of a functional dissociation between the dorsomedial PFC and the ventromedial PFC in the role.
通过评估向大鼠内侧前额叶皮质（PFC）腹侧局部注射多巴胺能药物对操作性延迟位置匹配（DMTP）任务的影响，研究了前额叶皮质内侧多巴胺能神经支配在短期记忆功能中的假定作用。在向腹内侧前额叶皮质双侧微量注射几剂多巴胺受体激动剂阿扑吗啡（APO）或多巴胺受体拮抗剂顺式氟哌噻吨（FLU）后，对两组不同的大鼠进行了测试。此外，在注射几剂毒蕈碱受体拮抗剂东莨菪碱（SCO）和多巴胺D1受体拮抗剂SCH-23390（SCH）后，对所有动物进行了测试。所测试的药物对DMTP性能有不同的影响。APO对反应准确性没有影响，尽管它剂量依赖性地影响鼻触活动和反应潜伏期。FLU和SCH均诱导了剂量依赖性但与延迟无关的反应准确性下降，同时反应潜伏期增加，鼻触频率降低，导致一些动物在注射两种药物的最高剂量后停止反应。相比之下，向腹内侧前额叶皮质注射SCO会导致剂量和延迟依赖性的反应准确性下降，且仅伴有反应潜伏期增加。综上所述，这些结果为胆碱能而非多巴胺能机制参与大鼠内侧前额叶皮质支持的短期记忆提供了额外支持，并且不支持背内侧前额叶皮质和腹内侧前额叶皮质在该作用中的功能分离。
