Saha N, Datta H, Sharma P L
Department of Pharmacology, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
Pharmacology. 1991;42(1):10-4. doi: 10.1159/000138762.
The effects of morphine on memory have been shown to be dependent on the strain of animal used and on the experimental parameters. Memory was assessed in a passive avoidance task using Swiss albino (ICRC) mice. Morphine at doses of 1, 3 and 10 mg kg-1 was administered immediately after foot shock (memory retention) or 23.5 h after foot shock (memory retrieval). Retest step-down latencies measured 24 h later showed that morphine did not affect memory retention but dose-dependently impaired retrieval of memory. Administration of naloxone 0.1 mg kg-1 antagonised the effects of morphine and impaired memory retention. Propranolol 0.3 mg kg-1 along with morphine 3 mg kg-1 impaired memory retention only while haloperidol 0.1 mg kg-1 improved the impairment of memory retrieval caused by morphine 3 mg kg-1. Glucose did not alter the effects of morphine on memory. There was no per se effect of morphine, naloxone, propranolol, glucose and haloperidol on memory at the doses used. The effect of morphine on memory retention is mediated by opioid mechanisms; however, adrenergic and dopaminergic mechanisms possibly modulate retention and retrieval of memory, respectively.
吗啡对记忆的影响已被证明取决于所用动物的品系和实验参数。使用瑞士白化（ICRC）小鼠通过被动回避任务评估记忆。在足部电击后立即（记忆保持）或足部电击后23.5小时（记忆提取）给予剂量为1、3和10 mg kg-1的吗啡。24小时后测量的再测试步下潜伏期表明，吗啡不影响记忆保持，但剂量依赖性地损害记忆提取。给予0.1 mg kg-1的纳洛酮可拮抗吗啡的作用并损害记忆保持。0.3 mg kg-1的普萘洛尔与3 mg kg-1的吗啡一起仅损害记忆保持，而0.1 mg kg-1的氟哌啶醇可改善3 mg kg-1吗啡引起的记忆提取损害。葡萄糖不会改变吗啡对记忆的影响。在所使用的剂量下，吗啡、纳洛酮、普萘洛尔、葡萄糖和氟哌啶醇本身对记忆没有影响。吗啡对记忆保持的影响由阿片类机制介导；然而，肾上腺素能和多巴胺能机制可能分别调节记忆的保持和提取。
