Takahashi R N, Singer G
Pharmacol Biochem Behav. 1980 Dec;13(6):877-81. doi: 10.1016/0091-3057(80)90222-1.
Previous findings have shown that naive rats self-inject IV delta 9-THC 12.5 microgram/kg/infusion in the presence of a FT-1 non contingent food delivery schedule. In the present study the effects of three different body weight levels, 80%, 90% and 100%, with and without a FT-1 food delivery schedule, were examined on the THC self-injection behavior. Results confirmed that 80% body weight plus the FT-1 schedule condition leads to the highest intake of THC. In a further experiment, naive rats acquired THC self-injection at 80% body weight with a FT-1 schedule. Rats were then allowed to regain body weight to their free feeding level and were tested again in the same basic paradigm. Animals recovering body weight did not maintain the self-injection rates. The data indicate that the environmental conditions necessary in the acquisition phase are also required to maintain intake of THC 12.5 microgram/kg/infusion.
先前的研究结果表明，在非偶然的FT-1食物递送时间表下，未接触过药物的大鼠会自我注射静脉注射剂量为12.5微克/千克/次的δ9-四氢大麻酚。在本研究中，研究了三种不同体重水平（80%、90%和100%）在有和没有FT-1食物递送时间表的情况下，对四氢大麻酚自我注射行为的影响。结果证实，80%体重加上FT-1时间表条件导致四氢大麻酚摄入量最高。在进一步的实验中，未接触过药物的大鼠在80%体重和FT-1时间表下获得了四氢大麻酚自我注射行为。然后让大鼠恢复到自由进食水平的体重，并在相同的基本范式中再次进行测试。恢复体重的动物没有维持自我注射率。数据表明，获取阶段所需的环境条件对于维持12.5微克/千克/次四氢大麻酚的摄入量也是必需的。
