Impact of prenatal lipopolysaccharide exposure on the development of rats

Abstract The intrauterine environment is infl uenced by several factors, genetic or environmental, which are essential in understanding the pathophysiological mechanisms of some diseases. In this study, the aim was to investigate the impact of prenatal lipopolysaccharide exposure on the development of rats. Fifty pregnant rats received intraperitoneal administration of lipopolysaccharide (100 µg/kg), or saline at the same dose, on the 9.5th day of pregnancy. The offspring of these rats were analyzed for indicators of brain and somatic development and maturation of physical characteristics. Refl ex ontogenesis was also analyzed by vibrissae placement, negative geotaxis, palmar grasp, precipice aversion, decubitus recovery and acceleration reaction. Administration of lipopolysaccharide on the 9.5th gestational day caused delayed opening of the auditory pavilion, reduction in the length of the tail, body, cranial axes, and body weight. Thus, maternal infections can interfere in the intrauterine environment, impairing functional and structural aspects of the central nervous system, as well as the maturation of physical characteristics.摘要：宫内环境受遗传、环境等多重因素影响，此类因素是解析部分疾病病理生理机制的核心要素。本研究旨在探究产前脂多糖（lipopolysaccharide）暴露对大鼠生长发育的影响。实验选取50只孕鼠，于妊娠第9.5天对其实施腹腔给药（intraperitoneal administration），分别注射脂多糖（100 μg/kg）或等剂量生理盐水。随后对两组孕鼠的子代开展检测分析，测定其脑部与躯体发育水平、躯体特征成熟度相关指标；同时通过触须放置反射、负趋地性反射（negative geotaxis）、掌抓握反射、悬崖回避反射、卧位恢复反射（decubitus recovery）及加速度反应（acceleration reaction），评估仔鼠的反射发育（reflex ontogenesis）情况。结果表明，于妊娠第9.5天给予脂多糖可导致仔鼠听觉篷（auditory pavilion）张开延迟，同时使其尾长、体长、颅轴长度及体重均出现下降。综上，母体感染可干扰宫内环境，损害中枢神经系统的功能与结构，同时延缓躯体特征的成熟进程。