Najam N, Panksepp J
Department of Psychology, Bowling Green State University, OH 43403.
Pharmacol Biochem Behav. 1989 Jul;33(3):539-44. doi: 10.1016/0091-3057(89)90383-3.
Chronic morphine treatment of newborn Long-Evans rat pups between 3-26 days of age (thrice daily starting with 0.5 mg/kg, increased daily by 0.5 mg/kg to 10 mg/kg) led to lags of 1 to 3 days in physical development (body weights and eye opening times) and motor coordination (catalepsy test, grasping, swimming). Chronic naloxone treatment (5 mg/kg administered thrice daily from day 3-26), in contrast, led to modest gains in development on a number of measures (body weights, vaginal opening). Morphine animals also lagged behind controls and naloxone-tested animals in social behaviors, such as homing and play. Chronic naloxone did not block or retard social development; in fact naloxone-treated animals exhibited more rapid acquisition of homing behavior than controls.
对3至26日龄的新生Long-Evans大鼠幼崽进行慢性吗啡治疗（每日三次，起始剂量为0.5毫克/千克，每日增加0.5毫克/千克至10毫克/千克）导致身体发育（体重和睁眼时间）和运动协调能力（僵住症测试、抓握、游泳）滞后1至3天。相比之下，慢性纳洛酮治疗（从第3天至第26天每日三次给予5毫克/千克）在多项指标（体重、阴道开口）上使发育有适度增加。吗啡处理的动物在社交行为方面，如归巢和玩耍，也落后于对照组和接受纳洛酮测试的动物。慢性纳洛酮并未阻碍或延缓社交发育；事实上，接受纳洛酮治疗的动物比对照组更快地习得归巢行为。
