Alpha2- Adrenergic blockers restore noise-induced biochemical and cognitive disorders

Abstract

Noise-induced stress causes central nervous system dysfunction and neurotransmission impairment in the brain and changes hormone levels which potentially result in psychological and behavioral problems. Considering the significance of the potential negative outcome of the chronic stress, the aim of our investigation was to study the level of inositol triphosphate (IP3) in the mitochondrial fraction of the brain (MFB), behavioral characteristics and the effects of the α2-adrenoblockers beditin and mesedin to reveal their antioxidative effect during noise exposure. The open field tests were used in order to evaluate the behavioral states of the rats. Investigations were carried out on albino rats divided into 4 groups. The 1st group of rats served as a control. The 2nd, 3rd and 4th groups were exposed to 91 dBA of noise; the duration of exposure was 8 hours per day for 60 days. The 3rd group was injected with beditin and the 4th group with mesedin, both intraperitoneally and repeatedly. According to our results, the chronic exposure to high-level noise leads to the decreased level of IP3 resulting development of oxidative stress and metabolism imbalance. The open field test revealed that chronic noise exposure caused noise durationdependent delay in the locomotor and behavioral activity. Intensity of these changes were dependent on the duration of noise exposure. The administration of α2-adrenoblockers to the noise-exposed animals had a regulatory effect on the studied parameters under the conditions of chronic acoustic stress.