Department of Psychology, Wayne State University, Detroit, Michigan, USA.
Department of Psychology, University of Wisconsin-Stevens Points, Stevens Point, Wisconsin, USA.
Dev Psychobiol. 2021 Dec;63(8):e22212. doi: 10.1002/dev.22212.
Preterm births accounted for over 10% of all U.S. live births in 2019 and the rate is rising. Neonatal stressors, especially procedural pain, experienced by preterm infants in the neonatal intensive care unit (NICU) have been associated with neurodevelopmental impairments. Parental care can alleviate stress during stressful or painful procedures; however, infants in the NICU often receive reduced parental care compared with their peers. Animal studies suggest that decreased maternal care similarly impairs neurodevelopment but also influences the effects of neonatal pain. It is important to mimic both stressors in animal models of neonatal stress exposure. In this study, researchers investigated the individual and combined impact of neonatal pain and maternal isolation on reelin protein levels and cellular proliferation in the hippocampal dentate gyrus of 8 days old and adult rats. Exposure to either stressor individually, but not both, increased reelin levels in the dentate gyrus of adult females without significantly altering reelin levels in adult males. However, cell proliferation levels at either age were unaffected by the early-life stressors. These results suggest that each early-life stressor has a unique effect on markers of brain development and more research is needed to further investigate their distinct influences.
2019 年，早产儿占美国所有活产儿的 10%以上，且这一比例还在上升。新生儿重症监护病房（NICU）中早产儿所经历的新生儿应激源，尤其是程序性疼痛，与神经发育损伤有关。父母的照顾可以减轻早产儿在经历有压力或痛苦的医疗程序时的压力；然而，与同龄人相比，NICU 中的婴儿往往得到的父母照顾较少。动物研究表明，减少母亲的照顾同样会损害神经发育，但也会影响新生儿疼痛的影响。在新生儿应激暴露的动物模型中模拟这两种应激源很重要。在这项研究中，研究人员研究了新生疼痛和母亲隔离对 8 天大和成年大鼠海马齿状回 reelin 蛋白水平和细胞增殖的单独和联合影响。单独暴露于任一应激源，但不是两者都有，增加了成年雌性大鼠齿状回中的 reelin 水平，而对成年雄性大鼠的 reelin 水平没有显著影响。然而，在任何年龄，细胞增殖水平都不受早期生活应激源的影响。这些结果表明，每个早期生活应激源对大脑发育的标志物都有独特的影响，需要进一步研究以更深入地调查它们的不同影响。
