Colomina M T, Albina M L, Domingo J L, Corbella J
Department of Psychology, Rovira i Virgili University, Tarragona, Spain.
Physiol Behav. 1997 Mar;61(3):455-9. doi: 10.1016/s0031-9384(96)00462-3.
The present study combined maternal restraint stress with exposure to 2 environmental toxic elements, mercury and arsenic, given to mice concurrently with the restraint period (1000-1200 h, gestational days 15-18). Two groups of animals were given, by gavage, methylmercury chloride (MMC) (2 mg/kg/day), and 2 additional groups received sodium arsenite (10 mg/kg/day) on days 15-18 of gestation. Immediately after MMC or arsenite exposure, 1 group of MMC-treated mice and 1 group of arsenite-treated animals were restrained for 2 h/day. Control groups included restrained and unrestrained pregnant mice nonexposed to MMC or arsenite. All animals were allowed to deliver and wean their offspring. Pups were evaluated for physical development, as well as for behavioral effects. Except for a significant decrease in pivoting on postnatal day 9 in the group exposed to arsenite plus restraint, no other MMC- or arsenite-induced behavioral changes were noted in unrestrained or restrained groups. Although a significant delay in pinna detachment and in eye opening was observed in pups of the group exposed to arsenite and restraint, the development landmarks were not affected by restraint in the MMC-treated animals. Although maternal stress reduced body weight gain in the dams exposed to MMC plus restraint, a significant interaction between maternal stress and MMC could not be established for developmental toxicity. These preliminary results, combined with those of previous investigations, show that stress can significantly exacerbate the adverse effects of environmental toxic elements.
本研究将母体束缚应激与两种环境有毒元素汞和砷的暴露相结合，在束缚期（妊娠第15 - 18天的1000 - 1200时）同时给予小鼠。两组动物在妊娠第15 - 18天通过灌胃给予氯化甲基汞（MMC）（2毫克/千克/天），另外两组给予亚砷酸钠（10毫克/千克/天）。在MMC或亚砷酸盐暴露后，立即对一组经MMC处理的小鼠和一组经亚砷酸盐处理的动物每天束缚2小时。对照组包括未暴露于MMC或亚砷酸盐的束缚和未束缚的怀孕小鼠。所有动物均被允许分娩并抚养其后代。对幼崽进行身体发育以及行为影响的评估。除了在暴露于亚砷酸盐加束缚的组中，出生后第9天的转身行为显著减少外，在未束缚或束缚组中未观察到其他MMC或亚砷酸盐诱导的行为变化。虽然在暴露于亚砷酸盐和束缚的组的幼崽中观察到耳廓分离和睁眼明显延迟，但在经MMC处理的动物中，发育里程碑不受束缚的影响。虽然母体应激降低了暴露于MMC加束缚的母鼠的体重增加，但对于发育毒性，无法确定母体应激与MMC之间存在显著的相互作用。这些初步结果与先前的研究结果相结合，表明应激可显著加剧环境有毒元素的不良影响。
