Music exposure differentially alters the levels of brain-derived neurotrophic factor and nerve growth factor in the mouse hypothalamus

It has been reported that music may have physiological effects on blood pressure, cardiac heartbeat, respiration, and improve mood state in people affected by anxiety, depression and other psychiatric disorders. However, the physiological bases of these phenomena are not clear. Hypothalamus is a brain region involved in the regulation of body homeostasis and in the pathophysiology of anxiety and depression through the modulation of hypothalamic-pituitary-adrenal (HPA) axis. Hypothalamic functions are also influenced by the presence of the neurotrophins brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF), which are proteins involved in the growth, survival and function of neurons in the central nervous system. The aim of this study was to investigate the effect of music exposure in mice on hypothalamic levels of BDNF and NGF. We exposed young adult mice to slow rhythm music (6 It per day; mild sound pressure levels, between 50 and 60 dB) for 21 consecutive days. At the end of the treatment mice were sacrificed and BDNF and NGF levels in the hypothalamus were measured by enzyme-linked immunosorbent assay (ELISA). We found that music exposure significantly enhanced BDNF levels in the hypothalamus. Furthermore, we observed that music-exposed mice had decreased NGF hypothalamic levels. Our results demonstrate that exposure to music in mice can influence neurotrophin production in the hypothalamus. Our findings also suggest that physiological effects of music might be in part mediated by modulation of neurotrophins. (C) 2007 Elsevier Ireland Ltd. All rights reserved.