Aikawa H, Suzuki K, Misawa T, Momotani H, Shigeta S
Sangyo Igaku. 1986 Nov;28(6):428-37. doi: 10.1539/joh1959.28.428.
Effects of administration of lead acetate on Sidman avoidance behavior were assessed in juvenile and adult rats which were obtained by continued selective breeding and which have a high level avoidance ability and small individual differences (THA rat: Tokai high avoider rat). THA rats were administered lead acetate solution at 200-300 mg/kg/day as Pb until 7 wk of age through maternal milk before weaning from mothers which had been administered lead acetate from the 13th day of gestation and per os by gastric tube after weaning. Three series of Sidman avoidance behavior tests were conducted from 49th, 100th and 150th day after birth each for 10 d, 1 h every day. In the first series, a significant delay of shock avoidance acquisition was observed in lead-administered male rats compared with the control subjects, while no acquisition delay was seen in female rats. The lead administered male rats could be divided into two groups with different response patterns; a low susceptible group (LSG) which exhibited as good acquisition rate from the beginning similar to the control rats and a high susceptible group (HSG) which showed a significant delay and individual differences. In the 2nd test series, very high avoidance rates were obtained in all the test groups except in male HSG, but in the 3rd test series, male HSG also attained a final acquisition of high avoidance rate. There was no developmental variation between the groups nor difference in lead contents of the organs of the exposed group. Useful characteristics of THA rats for behavioral toxicology are discussed.
通过持续选择性育种获得的、具有高回避能力且个体差异小的幼年和成年大鼠（THA大鼠：东海高回避大鼠）被用于评估醋酸铅给药对西德曼回避行为的影响。在妊娠第13天开始给母鼠腹腔注射醋酸铅，幼崽在断奶前通过母乳接受200 - 300 mg/kg/天的醋酸铅溶液（以铅计），断奶后通过胃管经口给药，直至7周龄。在出生后的第49天、第100天和第150天分别进行了三个系列的西德曼回避行为测试，每个系列持续10天，每天测试1小时。在第一个系列中，与对照组相比，接受铅处理的雄性大鼠在回避电击习得方面出现了显著延迟，而雌性大鼠未见习得延迟。接受铅处理的雄性大鼠可分为两组，反应模式不同；一组是低敏感组（LSG），从一开始就表现出与对照大鼠相似的良好习得率，另一组是高敏感组（HSG），表现出显著延迟和个体差异。在第二个测试系列中，除雄性HSG外，所有测试组的回避率都很高，但在第三个测试系列中，雄性HSG最终也获得了高回避率。各实验组之间没有发育差异，暴露组器官中的铅含量也没有差异。文中讨论了THA大鼠在行为毒理学研究中的有用特性。
