Sinden J D, Allen Y S, Rawlins J N, Gray J A
MRC Brain, Behaviour and Psychiatry Research Group, Institute of Psychiatry, London, U.K.
Behav Brain Res. 1990 Jan 22;36(3):229-49. doi: 10.1016/0166-4328(90)90061-i.
Rats were trained to criterion performance in 2-lever operant conditional memory tasks that required them to follow either a Win-stay/Lose-shift, or else a Win-shift/Lose-stay response rule. Substantial impairments in performance of both pretrained conditional tasks were seen following ibotenic acid lesions of the nucleus basalis, but not of the globus pallidus. The deficit in both tasks was apparent at all inter-response retention intervals, indicating that nucleus basalis lesions produced a general impairment in the performance of the complex conditional operant tasks, and not a specific deficit in short-term memory. The nucleus basalis lesion rats were then divided into groups matched for equivalent performance. One group was given cell suspension grafts into neocortex of E15 cholinergic-rich forebrain tissue; a second group was given similar grafts of E17 hippocampal tissue; and a third group was given sham transplants. Testing beginning 3 months post-transplant showed that there was no evidence of recovery of performance on these tasks in the cholinergic-rich transplanted groups compared to the controls. However, the rats with cholinergic-rich transplants subsequently showed a significant improvement in retention of a step-through passive avoidance task. The results indicate that either cholinergic deafferentation of the neocortex is not critical for the observed deficits in the operant conditional tasks, or recovery of function following cholinergic-rich transplants is task-specific, in that more complex cognitive tasks may require different levels of graft-host neural integration.
大鼠在双杠杆操作性条件记忆任务中接受训练，直至达到标准表现，这些任务要求它们遵循“赢则停留/输则转换”或“赢则转换/输则停留”的反应规则。在基底核注射鹅膏蕈氨酸损伤后，两种预训练条件任务的表现均出现显著受损，但苍白球损伤后未出现这种情况。在所有反应间保持间隔中，两种任务的缺陷都很明显，这表明基底核损伤导致复杂条件操作性任务的表现普遍受损，而非短期记忆的特定缺陷。然后将基底核损伤的大鼠分成表现相当的几组。一组在新皮质中植入E15富含胆碱能的前脑组织细胞悬液；第二组植入类似的E17海马组织移植物；第三组进行假移植。移植后3个月开始测试，结果显示，与对照组相比，富含胆碱能的移植组在这些任务上没有表现恢复的迹象。然而，富含胆碱能移植的大鼠随后在一步通过被动回避任务的保持方面有显著改善。结果表明，要么新皮质的胆碱能传入缺失对操作性条件任务中观察到的缺陷并不关键，要么富含胆碱能移植后的功能恢复是任务特异性的，因为更复杂的认知任务可能需要不同水平的移植物-宿主神经整合。
