Risinger F O, Cunningham C L
Department of Behavioral Neuroscience and Portland Alcohol Research Center, L470, Oregon Health Sciences University, 3181 SW Sam Jackson Park Road, Portland, OR 97201-3098, USA.
Pharmacol Biochem Behav. 2000 Sep;67(1):17-24. doi: 10.1016/s0091-3057(00)00310-5.
Genetic differences in lithium-induced conditioned aversion were examined using both place- and taste-conditioning procedures. In the place-conditioning procedure, adult male C57BL/6J (B6) and DBA/2J (D2) mice were exposed to a differential conditioning procedure in which each mouse received four 30-min pairings of a distinctive floor cue immediately after IP injections of either 0.75, 1.5, or 3. 0 mEq/kg LiCl. A different floor cue was paired with saline injections. A separate group of control mice received saline injections paired with both floor types. Subsequent floor preference testing revealed greater conditioned aversion in D2 mice compared to B6 mice in groups receiving 3.0 mEq/kg LiCl. Lower LiCl doses did not produce conditioning in either strain. In a conditioned taste-aversion procedure, fluid-restricted mice received four trials in which access to 0.2 M NaCl solution was followed by IP injection of either 0.75, 1.5, 3.0, or 6.0 mEq/kg LiCl. D2 mice showed stronger conditioned taste aversion than B6 mice at all doses, suggesting that taste conditioning may be a more sensitive index of aversive drug sensitivity than place conditioning. These findings are not well explained by strain differences in general learning ability or by strain differences in stimulus salience or innate preference. Rather, these data appear more consistent with previous studies showing strain differences in lithium pharmacokinetics and in general sensitivity to aversive events.
利用位置条件化和味觉条件化程序研究了锂诱导的条件性厌恶中的基因差异。在位置条件化程序中,成年雄性C57BL/6J(B6)和DBA/2J(D2)小鼠接受差异条件化程序,即每只小鼠在腹腔注射0.75、1.5或3.0 mEq/kg LiCl后立即接受四次30分钟的独特地面线索配对。另一种不同的地面线索与生理盐水注射配对。另一组对照小鼠接受与两种地面类型都配对的生理盐水注射。随后的地面偏好测试显示,在接受3.0 mEq/kg LiCl的组中,D2小鼠比B6小鼠表现出更大的条件性厌恶。较低剂量的LiCl在两种品系中均未产生条件化。在条件性味觉厌恶程序中,限水小鼠接受四次试验,在接触0.2 M NaCl溶液后腹腔注射0.75、1.5、3.0或6.0 mEq/kg LiCl。在所有剂量下,D2小鼠比B6小鼠表现出更强的条件性味觉厌恶,这表明味觉条件化可能比位置条件化更能敏感地反映厌恶药物敏感性。这些发现不能通过一般学习能力的品系差异、刺激显著性或先天偏好的品系差异得到很好的解释。相反,这些数据似乎与之前的研究更一致,这些研究表明锂药代动力学和对厌恶事件的一般敏感性存在品系差异。