title: Impact of environmental noise on growth and neuropsychological development of newborn rats.
abstract: We aimed to investigate the effects of environmental noise exposure on the growth and neuropsychological development in neonatal rats. Twenty-four postnatal 7-day-old Sprague-Dawley rats were randomly assigned into control, high-noise and reduced noise groups. The rats in the high-noise group were exposed to 90 dB white noise, and those in the control group were grown under standard condition, while those in the reduced noise group were exposed to standard condition with sound-absorbing cotton. Ten, 15, and 20 days post noise exposure, both the body weight and length of the rats in high-noise group were lower than those in the control and reduced noise groups, respectively. The secretion of growth hormone was significantly decreased in the rats exposed to high noise environment, compared to those exposed to standard condition and reduced noise. More interestingly, the swimming distance was apparently increased and the swimming speed was significantly decreased in high-noise group compared with those in control and reduced noise groups. Importantly, the mRNA and protein levels of SYP in the rats hippocampus were significantly decreased in high-noise group compare with those in control and reduced noise groups. Similarly, the positive expression of SYP in the CA1 region of hippocampus was also significantly decreased in the high noise group rats. In conclusion, our results demonstrated that high noise exposure could decrease the production of growth hormone and SYP in neonatal rats, which may retard the growth of weight and length and the capability of learning and memory.
authors.affiliation: Department of Pediatrics, Xinqiao Hospital, The Third Military Medical University, Chongqing, 400037, People's Republic of China.
authors.forename: Yanyan
authors.initials: Y
authors.lastname: Zheng
authors.forename: Meng
authors.initials: M
authors.lastname: Meng
authors.forename: Congmin
authors.initials: C
authors.lastname: Zhao
authors.forename: Wei
authors.initials: W
authors.lastname: Liao
authors.forename: Yuping
authors.initials: Y
authors.lastname: Zhang
authors.forename: Liyan
authors.initials: L
authors.lastname: Wang
authors.forename: Enyi
authors.initials: E
authors.lastname: Wen
mesh_terms: D000818:Animals; D001835:Body Weight / Q000502:physiology; D004777:Environment; D006624:Hippocampus / Q000378:metabolism / Q000502:physiology*; D008297:Male; D018782:Maze Learning / Q000502:physiology*; D009622:Noise; D051381:Rats; D017207:Rats, Sprague-Dawley; D013550:Swimming / Q000502:physiology; D016708:Synaptophysin / Q000378:metabolism
chemical_list: D016708:Synaptophysin
keywords: growth hormone; learning and memory; noise; synaptophysin