Schulze G E, Paule M G
Division of Reproductive and Developmental Toxicology National Center for Toxicological Research, Jefferson, AR 72079.
Pharmacol Biochem Behav. 1991 Jan;38(1):77-83. doi: 10.1016/0091-3057(91)90592-p.
The acute effects of morphine sulfate were assessed using a battery of complex food-reinforced operant tasks that included temporal response differentiation (TRD, n = 5), delayed matching-to-sample (DMTS, n = 6), progressive ratio (PR, n = 9), incremental repeated acquisition (IRA, n = 9), and conditioned position responding (CPR, n = 7) tasks. Performance in these tasks is thought to depend upon specific brain functions such as time perception (TRD), learning (IRA), short-term memory and attention (DMTS), color and position discrimination (CPR), and motivation to work for food (PR). Morphine sulfate (0.1-5.6 mg/kg IV), given 15 min presession, produced significant dose-dependent decreases in the number of reinforcers obtained in each task. Response accuracy was significantly decreased at doses greater than or equal to 1.0 mg/kg for TRD when compared to saline injections. Accuracy was not consistently affected in any other task in the test battery. Response rates decreased or response latencies increased significantly at doses of 1.0 mg/kg and above for the PR task, at 3.0 mg/kg and above for the IRA and TRD tasks, and only at the highest dose 5.6 mg/kg in the CPR and DMTS tasks. Percent task completed was decreased following doses of 1.0 mg/kg and higher for the IRA, PR and TRD tasks, at doses of 3.0 mg/kg and higher for the DMTS task, and at the high dose of 5.6 mg/kg for the CPR task. These results indicate that in monkeys, the performance of operant tasks designed to model learning ability (IRA), time perception (TRD) and motivation (PR) are more sensitive to the disruptive effects of morphine than is performance in tasks designed to model short-term memory and attention (DMTS). The task which models color and position discrimination (CPR) was the least sensitive to disruption by morphine.
使用一系列复杂的食物强化操作性任务评估硫酸吗啡的急性效应，这些任务包括时间反应分化（TRD，n = 5）、延迟匹配样本（DMTS，n = 6）、渐进比率（PR，n = 9）、增量重复习得（IRA，n = 9）和条件位置反应（CPR，n = 7）任务。这些任务中的表现被认为取决于特定的脑功能，如时间感知（TRD）、学习（IRA）、短期记忆和注意力（DMTS）、颜色和位置辨别（CPR）以及为获取食物而工作的动机（PR）。在实验前15分钟静脉注射硫酸吗啡（0.1 - 5.6毫克/千克），导致每个任务中获得的强化物数量出现显著的剂量依赖性减少。与注射生理盐水相比，当剂量大于或等于1.0毫克/千克时，TRD任务中的反应准确性显著降低。在测试组的任何其他任务中，准确性并未受到持续影响。对于PR任务，在剂量为1.0毫克/千克及以上时反应率降低或反应潜伏期显著增加；对于IRA和TRD任务，在剂量为3.0毫克/千克及以上时如此；而在CPR和DMTS任务中，仅在最高剂量5.6毫克/千克时出现这种情况。对于IRA、PR和TRD任务，在剂量为1.0毫克/千克及以上时，完成任务的百分比降低；对于DMTS任务，在剂量为3.0毫克/千克及以上时降低；对于CPR任务，在高剂量5.6毫克/千克时降低。这些结果表明，在猴子中，旨在模拟学习能力（IRA）、时间感知（TRD）和动机（PR）的操作性任务的表现比旨在模拟短期记忆和注意力（DMTS）的任务表现对吗啡的干扰作用更敏感。模拟颜色和位置辨别的任务（CPR）对吗啡干扰的敏感性最低。
