Prenatal exposure to noise stress: Anxiety, impaired spatial memory, and deteriorated hippocampal plasticity in postnatal life

Abstract

Sound pollution is known as an annoying phenomenon in modern life. Especially, development of organisms during fetal life is more sensitive to environmental tensions. To address a link between the behavioral and electrophysiological aspects of brain function with action of hypothalamus-pituitary-adrenal (HPA) axis in stressed animals, this study was carried out on the male Wistar rats prenatally exposed to sound stress. Groups of pregnant rats were exposed to noise stress for 1, 2, and 4 hour(s). The degree of anxiety and the spatial memory were evaluated by elevated plus maze and Morris water maze, respectively. Basic synaptic activity and long-term potentiation (LTP) induction were assessed in the CA3-CA1 pathway of hippocampus. The serum level of corticosterone was measured in the pregnant mothers and the offspring. The behavioral experiments appeared that the stressed animals performed considerably weaker than the control rats. The prenatal stress negatively affected the basic synaptic responses and led to a lower level of LTP. The pregnant animals showed an increased serum corticosterone in comparison with the nonpregnant females. Also the offspring exposed to the noise stress had a more elevated level of corticosterone than the control rats. Our findings indicate that the corticosterone concentration changes markedly coincides the results of behavioral and electrophysiological experiments. We conclude that, similar to other environmental stresses, the sound stress during fetal life efficiently disturbs both cognitive abilities and synaptic activities. The changes in action of HPA axis may contribute to problems of the brain function in the prenatally stress exposed animals.

Prenatal Stress Alters Hippocampal Neuroglia and Increases Anxiety in Childhood

“…This study also found that both sexes exposed to prenatal stress spent less time in the inner zone of the open-field arena during behavioural testing, which supports a role for prenatal stress in increasing vulnerability to disorders leading to anxiety-like behaviours [33,34]. With an increasing number of studies now supporting the striking association between prenatal stress exposure and the development of anxiety-related disorders in offspring [35,36,37], there appears to be a role for the sex of the offspring in determining the severity of the outcomes associated with prenatal stress exposure [33,38,39]. Interestingly, this was not the case in the current study design.…”

The impact of early postnatal environmental enrichment on maternal care and offspring behaviour following weaning

“…However, self-grooming can be seen as a de-arousing activity which is increased in anxious rats (Spruijt et al 1992;Kalueff and Tuohimaa 2005;Voigt et al 2005). Although the present design did not allow for analysing anxiety-related behaviour in dams, earlier studies demonstrated that offspring from dams previously exposed to a stress-inducing environment will show stronger responses to anxiogenic stimuli (Plotsky and Meaney 1993;Ladd et al 2000;Wei et al 2010;Maccari et al 2014;Barzegar et al 2015). Alternatively, grooming could also be associated with the significantly increased feeding as observed in the dams in the present study.…”

Sex-Specific Effects of Prenatal Stress on Memory and Markers of Neuronal Activity in Juvenile Rats

“…Many preclinical studies have attempted to find experimental support for these observations but the results are not consistent. Prenatal stress was shown to slow the rate of acquisition of spatial memory in adult male rats [4,5,6,7,8] and to decrease hippocampal long-term potentiation [9]. However, others have found that prenatal stress may also enhance spatial memory [10,11].…”