Fleming A S, Cheung U S, Barry M
Department of Psychology, Erindale College, University of Toronto, Mississauga, Ontario, Canada.
Behav Neural Biol. 1990 Jan;53(1):64-73. doi: 10.1016/0163-1047(90)90814-m.
Two studies were done to determine the effects of cycloheximide (CYX), a protein synthesis inhibitor, on maternal experience effects in rats. In the first study eight groups received a 2-h maternal experience 36 h after cesarean (c)-section and two groups received no post c-section experience. Among the experienced groups, two received icv injections of CYX or saline (SAL) 30 min before the maternal experience, two received CYX or SAL 10 min after the experience, and two received the injections 24 h after the experience. One inexperienced group received CYX and the other received SAL 36 h after c-section. Tests for maternal behavior occurred 10 days after c-section. CYX was not able to block or disrupt the "acquisition" or expression of ongoing maternal behavior during the 2-h experience phase. However, CYX was able to block the long-term "retention" of a 2-h maternal experience if the drug was present during or immediately after the experience, prior to "consolidation." The second study investigated the effects of CYX administered immediately after the maternal experience on the expression and retention of maternal behavior 4 and 6 days after c-section, to determine whether the hormonally mediated short-onset latencies of the 4-day group would be blocked by CYX. Eight groups of animals were tested for maternal behavior. Four were tested 4 days after c-section and four were tested 6 days after c-section. Within each of these groups two were experienced and two inexperienced; within each experience condition one group received CYX and one received SAL. Day 4 groups exhibited shorter onset latencies than Day 6 groups. There was also a CYX-SAL difference in maternal onset latencies among experienced Day 6 groups but not among Day 4 groups. These data indicate that the blocking effects of CYX can be seen only when hormonal priming of maternal behavior is no longer in evidence.
开展了两项研究以确定蛋白质合成抑制剂放线菌酮（CYX）对大鼠母体经验效应的影响。在第一项研究中，八组大鼠在剖宫产术后36小时接受了2小时的母体经验，两组未接受剖宫产术后的经验。在有经验的组中，两组在母体经验前30分钟接受了脑室内注射CYX或生理盐水（SAL），两组在经验后10分钟接受CYX或SAL，两组在经验后24小时接受注射。一组无经验的大鼠在剖宫产术后36小时接受CYX，另一组接受SAL。在剖宫产术后10天进行母体行为测试。CYX无法在2小时的经验阶段阻断或干扰正在进行的母体行为的“习得”或表现。然而，如果在经验期间或经验后立即、在“巩固”之前给予该药物，CYX能够阻断2小时母体经验的长期“保持”。第二项研究调查了在母体经验后立即给予CYX对剖宫产术后4天和6天母体行为的表现和保持的影响，以确定CYX是否会阻断4天组由激素介导的短启动潜伏期。八组动物接受了母体行为测试。四组在剖宫产术后4天进行测试，四组在剖宫产术后6天进行测试。在这些组中的每一组内，两组有经验，两组无经验；在每种经验条件下，一组接受CYX，一组接受SAL。第4天组的启动潜伏期比第6天组短。在有经验的第6天组中，CYX和SAL在母体启动潜伏期方面也存在差异，但在第4天组中没有。这些数据表明，只有当母体行为的激素启动不再明显时，才能看到CYX的阻断作用。
