title: 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.
authors.affiliation: Physiology Research Center, Kashan University of Medical Sciences, Kashan, Islamic Republic of Iran.
authors.forename: Marzieh
authors.initials: M
authors.lastname: Barzegar
authors.forename: Fatemeh Sadat
authors.initials: FS
authors.lastname: Sajjadi
authors.forename: Sayyed Alireza
authors.initials: SA
authors.lastname: Talaei
authors.forename: Gholamali
authors.initials: G
authors.lastname: Hamidi
authors.forename: Mahmoud
authors.initials: M
authors.lastname: Salami
mesh_terms: D000818:Animals; D001008:Anxiety Disorders / Q000503:physiopathology; D003345:Corticosterone / Q000097:blood; D004195:Disease Models, Animal; D019706:Excitatory Postsynaptic Potentials; D005260:Female; D006624:Hippocampus / Q000503:physiopathology; D017774:Long-Term Potentiation / Q000502:physiology; D008297:Male; D018782:Maze Learning / Q000502:physiology; D008569:Memory Disorders / Q000209:etiology / Q000503:physiopathology; D008839:Microelectrodes; D009622:Noise / Q000009:adverse effects*; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D011897:Random Allocation; D017208:Rats, Wistar; D065852:Spatial Memory / Q000502:physiology; D013315:Stress, Psychological / Q000503:physiopathology*; D009435:Synaptic Transmission / Q000502:physiology
chemical_list: D003345:Corticosterone
keywords: anxiety; fetal life; learning and memory; sound stress; synaptic plasticity