Behavioural and haematological studies on effects of lycopene in Wistar rats subjected to psychological stress

This study investigated the effects of prior lycopene supplementation on behaviour and haematology of Wistar rats subjected to psychological stress. Four groups of Wistar rats, each comprising seven animals were investigated: unstressed (U-Control), unstressed + lycopene (U+Lyco), stressed (SControl) and stressed + lycopene (S+Lyco). Olive oil was given by oral gavage to each rat in the groups, either singly or mixed with 10 mg/kg lycopene daily for two weeks. S-Control and S+Lyco groups were subjected to psychological stress followed by behavioural assessment using excitability score test. Blood samples were collected after sacrificing the animals and then analyzed. Psychological stress increased (P 0.05) erythrocyte MDA concentration. In conclusion, antioxidant properties of lycopene may be attenuating the effects of psychological stress on excitability score and erythrocytes of Wistar rats. Key words: excitability score, erythrocytes, total plasma proteins, fear stress, oxidative stress, antioxidant supplementation