Effects of chronic stress during pregnancy on sex-specific offspring emotional damage

Abstract

BackgroundStudies have shown that stress during pregnancy can affect the growth and development of fetuses and offspring, and this effect has sex differences, but the results are controversial, and there are few studies on the emotional damage of offspring of different sexes caused by stress during pregnancy.ObjectiveThis experiment is designed to observe the effect of chronic stress during pregnancy on emotional damage of offspring of different sexes.MethodsThirty-two SD female rats were randomly divided into a model group and a control group (16 rats in each group), 24 male rats were divided into a model mating group (n=16) and a control mating group (n=8). Each rat of the model group was reared in a single cage and received chronic unpredictable mild stress (CUMS) for 28 d, including hot water swimming for 5 min, cold water swimming for 5 min, tail pinching for 2 min, crowding for 24 h, moist bedding for 24 h, cage shaking for 30 min, and space restriction for 2 h. One stressor was administered daily and the same stressor did not repeat within 7 d. Blood was collected from the endocanthal vein of the two groups of female rats 1 d before and 1, 7, 14, 21, and 28 d after stress, the plasma was separated by centrifugation, and 131I radioimmunoassay was used to measure plasma corticosterone concentration. On postnatal day 21 (PND21), 16 offspring rats (half male and half male) were randomly selected from each group, their plasma corticosterone concentration was measured on PND28 and PND42, and their emotional damage was measured on PND42. ResultsThe plasma corticosterone levels of dams in the model group on the 14th, 21th, and 28th days of stress [(394.02±97.40), (444.12±90.43), and (463.71±107.75) μg·L−1] were higher than those in the control group [(285.63±81.64), (341.78±48.39), and (320.42±84.76) μg·L−1] (all P0.05). ConclusionChronic stress during pregnancy causes emotional damage to the offspring, and female offspring show depression-like behaviors.

Keywords

• stress during pregnancy
• chronic stress
• offspring
• emotional damage
• sex difference