de Castro Vera L S S, Destefani Camila R, Diniz Carlos, Poli Paola
Embrapa Meio Ambiente, Laboratório de Ecotoxicologia, Jaguariúna, SP, Brazil.
Neurotoxicology. 2007 Nov;28(6):1249-59. doi: 10.1016/j.neuro.2007.06.001. Epub 2007 Jun 14.
Although some studies have pointed to embryo/fetal toxicity at treatment levels that were not maternally toxic, knowledge about the potential toxic effects of the herbicide sulfentrazone is still limited. Since the results of these studies have raised some concern, the present work studied the effects of sulfentrazone maternal exposure on the physical and neurobehavioral endpoints in the development of rat pups. To accomplish that, the effects of the herbicide sulfentrazone (25 and 50mg/kg) were examined at two different developmental stages in rats: during the first 6 days of gestation, or in the organogenesis period (6-15 days). After parturition, pups were tested in a developmental test battery including measures of growth, maturational milestones, and neurobehavioral development. Maternal exposure to the herbicide resulted in significant alterations of the postnatal age at which the developmental milestones of ear and eye opening and testes descent were observed. There was a reduced weight gain rate in pups and their mothers when treated during the gestational period at the highest dose tested. Also, the functional state of the rat pup nervous system at different stages of postnatal development showed some neurodevelopmental delays in righting reflex, negative geotaxis, grip response, and motor coordination-locomotion and rearing (21-90 days of life) in the treated groups. Herbicide genotoxicity was investigated in fresh leukocytes both in mothers and pups using the comet assay: the data did not show any significant genotoxic effect induced by the herbicide. The findings of this study emphasize that sulfentrazone maternal exposure may lead to some neuromuscular and behavioral deficits in nursing pups.
尽管一些研究指出在未产生母体毒性的治疗水平下存在胚胎/胎儿毒性，但关于除草剂磺胺草唑潜在毒性作用的知识仍然有限。由于这些研究结果引发了一些担忧，本研究探讨了母体接触磺胺草唑对大鼠幼崽发育过程中身体和神经行为终点的影响。为实现这一目标，在大鼠的两个不同发育阶段检测了除草剂磺胺草唑（25和50mg/kg）的作用：妊娠的前6天，即器官形成期（6 - 15天）。分娩后，对幼崽进行了一系列发育测试，包括生长、成熟里程碑和神经行为发育的测量。母体接触该除草剂导致观察到耳、眼睁开和睾丸下降等发育里程碑的产后年龄出现显著变化。在妊娠期接受最高测试剂量处理时，幼崽及其母亲的体重增加率降低。此外，在出生后不同发育阶段，处理组大鼠幼崽神经系统的功能状态在翻正反射、负趋地性、抓握反应以及运动协调 - 移动和站立（出生后21 - 90天）方面表现出一些神经发育延迟。使用彗星试验在母鼠和幼崽的新鲜白细胞中研究了除草剂的遗传毒性：数据未显示该除草剂诱导的任何显著遗传毒性作用。本研究结果强调，母体接触磺胺草唑可能导致哺乳幼崽出现一些神经肌肉和行为缺陷。
