A Reduction of Rat Research Activity in the Open Field Test Caused by Carbon Nanotubes
For the first time the influence of MWCNT on functioning of higher nervous activity of mammals was observed. Wistar rats were fed (in forage) multi-walled carbon nanotubes (MWCNTs; d~9 nm, w(metals)< 2 % wt.; S(BET)=300 m2/g; aggregate size 0.005-0.1 mm) in a dosage of 500 mg/kg per day for 3 or 10 days.
MWCNTs were shown to have a considerable negative impact on research activity and anxiety of laboratory rats. Anxiety level of rats being fed MWCNTs started to grow as early as on the 3rd day and almost doubled after 10 days of exposure. Also MWCNTs decrease locomotor activity level by a factor of 2 after 3 days and by a factor of 4 after 10 days of exposure.
We assume that MWCNT may impact indirectly on the emotional status and central nervous system functioning via development of the inflammatory processes in body of rat. MWCNT pathogenicity can be caused by their structure (fibrous morphology and small size) via direct damage of cells as well as by impurities (Fe, Co, Al) and their high surface area which can block enzymes or other species.
This study was supported by Scientific Fund of Far Eastern Federal University (13-06-0318-m_a).