Akademik Veri Yönetim Sistemi
FRESENIUS ENVIRONMENTAL BULLETIN, cilt.25, sa.2, ss.612-622, 2016 (SCI-Expanded)
In this study, the effect of variable sized silica nanoparticles on the cardiac electrophysiology, mechanics, antioxidant activity, ultrastructure and genotoxicity in rats were investigated. Among five groups (6, 20, 50 nm, control and positive control for comet assay; n=7 for each group) treatment groups received intraperitonally 150 mu g/mL of silica nanoparticles for 28 days. Electrical and mechanical activities of heart were recorded using electrophysiological recording techniques. Malondialdehyde (MDA) levels, catalase (CAT) and superoxide dismutase (SOD) activities were measured using biochemical methodologies and transmission electron microscopic levels of heart samples were examined for all groups. Comet assay was performed on peripheral blood lympocytes. Heart rate significantly increased whereas amplitude and duration of T wave decreased in 6 and 20 nm groups as compared with control group. In 20 and 50 nm groups, P wave and QRS complex amplitude were significantly higher and contraction force were significantly lower than control. Duration of contraction decreased and contraction frequency increased in 6, 20 and 50 nm groups as compared with control group. There was no significant difference between control and silica nanoparticle received groups for MDA levels, CAT and SOD activities. Ultrastructurally, expansion in endoplasmic reticulum cisterns, disorganization and breaking off miyofibrils of myocytes were observed in 6, 20 and 50 nm groups. In genotoxicity study, tail length, tail intensity and tail moment of peripheral blood lympocytes significantly decreased in 20 and 50 nm groups as compared with positive control group. According to our results, exposure to different sizes SiNPs have a probable hazard potential for the cardiac system.