Department of Biology, East Carolina University, Greenville, NC 27858, USA.
Reprod Toxicol. 2013 Sep;40:69-75. doi: 10.1016/j.reprotox.2013.05.007. Epub 2013 Jun 2.
Effects and mechanisms of chronic exposure to low levels of nicotine is an area fundamentally important however less investigated. We employed the model organism Caenorhabditis elegans to investigate potential impacts of chronic (24h) and low nicotine exposure (6.17-194.5 μM) on stimulus-response, reproduction, and gene expressions. Nicotine significantly affects the organism's response to touch stimulus (p=0.031), which follows a dose-dependent pattern. Chronic nicotine exposure promotes early egg-laying events and slightly increased egg productions during the first 72 h of adulthood. The expressions of 10 (egl-10, egl-44, hlh-14, ric-3, unc-103, unc-50, unc-68, sod-1, oxi-1, and old-1) out of 18 selected genes were affected significantly. Other tested genes were cat-4, egl-19, egl-47, egl-5, lin-39, unc-43, pink-1, and age-1. Changes in gene expression were more evident at low dosages than at relatively high levels. Genes implicated in reproduction, cholinergic signaling, and stress response were regulated by nicotine, suggesting widespread physiological impacts of nicotine.
慢性低水平尼古丁暴露的影响及其机制是一个非常重要但研究较少的领域。我们采用模式生物秀丽隐杆线虫来研究慢性（24 小时）和低尼古丁暴露（6.17-194.5 μM）对刺激反应、繁殖和基因表达的潜在影响。尼古丁显著影响生物体对触摸刺激的反应（p=0.031），呈现剂量依赖性模式。慢性尼古丁暴露促进早期产卵事件，并在成年后的前 72 小时内略微增加产卵量。18 个选定基因中的 10 个（egl-10、egl-44、hlh-14、ric-3、unc-103、unc-50、unc-68、sod-1、oxi-1 和 old-1）的表达受到显著影响。其他测试的基因有 cat-4、egl-19、egl-47、egl-5、lin-39、unc-43、pink-1 和 age-1。在低剂量下，基因表达的变化比在相对高剂量下更为明显。涉及繁殖、胆碱能信号和应激反应的基因受到尼古丁的调节，表明尼古丁对广泛的生理影响。
