Reversibility of lead-induced depression of growth.
Reversibility of lead-induced depression of growth.
复制标题
铅引起的生长抑制的可逆性。
DOI：
10.1006/taap.1993.1215
复制
发表时间：
1993
影响因子：
3.8
通讯作者：
Paul Succop
中科院分区：
文献类型：
--
作者：
P. Hammond;Daniel J. Minnema;Paul Succop
这项调查的总体目标是确定铅(铅)的生长抑制效应是否可逆。实验动物模型为雌性断奶大鼠。在研究1中，一组动物接受10天的铅暴露，第二组动物再暴露21天，第三组动物作为对照。10天后停铅的动物在直线生长方面完全赶上对照组，但在体重增长方面只有部分赶上对照组。在铅暴露持续21天的动物中，直到研究结束时，与对照组相比，没有增长追赶。在研究2中，铅仅在暴露3天后终止。体重增加的抑制在停止暴露后1天内完全逆转。在研究3中，研究了单独营养不良(食物限制)的作用。体重增加立即受到抑制，与铅一样，线性增长(尾长)的下降直到后来才明显。当食物限制期为3天时，体重在免费获得食物后1天内赶上对照组。限食10天后，追赶也已完成，但速度较慢(7天)。就线性增长而言，追赶的证据是模棱两可的。结果表明，铅对生长影响的可逆性依赖于铅引起的食物消耗减少的持续时间，线性生长抑制比重量生长抑制更容易逆转。最后进行了一项研究(研究4)，以评估减少用水量在限制食物摄入量和生长方面的作用。对照组为(1)对照组，(2)饮水染铅组，(3)皮下注射铅组。只加铅显著降低了饮用水的耗水量。因此，口服铅的耗水量减少似乎与相关的食物消耗和生长抑制没有因果关系。
The overall objective of this investigation was to determine whether the growth-depressive effects of lead (Pb) are reversible. The animal model used was the female weanling rat. In Study 1, one group of animals was exposed to Pb for 10 days, a second group was exposed for an additional 21 days, and a third group of animals served as controls. Animals whose Pb was terminated after 10 days caught up completely with controls in terms of linear growth but only partially in terms of ponderal growth. There was no growth catch-up vis-à-vis controls among animals whose Pb exposure was continued for an additional 21 days, to the end of the study. In Study 2, Pb was terminated after only 3 days of exposure. Depression of body weight gain was completely reversed within 1 day after termination of exposure. In Study 3, the role of undernutrition alone (food restriction) was investigated. Depression of body weight gain was immediately apparent and, as with Pb, decrease in linear growth (tail length) was not apparent until later. Catch-up to controls in terms of weight was achieved within 1 day of free access to food when food restriction was for 3 days. Catch-up was also complete after 10 days of food restriction, but was slower (7 days). Evidence for catch-up in terms of linear growth was equivocal. It is concluded that the reversibility of the effects of Pb on growth is dependent on the duration of Pb-induced reduction of food consumption and that linear growth depression is more readily reversible than ponderal growth depression. A final study (Study 4) was undertaken to assess the role of reduced water consumption in limiting food intake and growth. Comparison groups were (1) control, (2) Pb via drinking water, and (3) Pb via sc osmotic pumps. Water consumption was significantly decreased only with Pb by drinking water. Thus, the reduced water consumption with Pb delivered orally seems not to be causally related to the associated depression of food consumption and growth.