Combined action of uranium and stress in the rat: Behavioral effects

M. Bellés^1,2, M.L. Albina^1,2, V. Linares^1,2, M. Gómez¹, D.J. Sánchez^1,2 and J.L. Domingo¹

¹Laboratory of Toxicology and Environmental Health, School of Medicine, Rovira i Virgili University, San Lorenzo 21, 43201 Reus, Spain
²Physiology Unit, School of Medicine, “Rovira i Virgili” University, San Lorenzo 21, 43201 Reus, Spain

The influence of restraint stress on uranium (U)-induced behavioral effects was assessed in adult male rats. Eight groups of animals received uranyl acetate dihydrate (UAD) in the drinking water at doses of 0, 10, 20 and 40 mg/kg/day during 3 months. Rats in four groups were concurrently subjected to restraint during 2 h per day throughout the study. At the end of the period of uranium exposure, the following behavioral tests were carried out: open field activity, passive avoidance, and the Morris water maze. Uranium concentrations in brain were also determined. Restraint stress did not affect significantly the uranium levels in brain of rats. However, at 20 and 10 mg/kg/day restraint significantly affected the total distance traveled in the open-field during the first and third periods tested respectively, while no significant differences between groups were observed on the passive avoidance test. In the Morris water maze test, the influence of restraint was only significant on the latency time measured on day 3 in rats exposed at 10 mg/kg/day. Although the results of the present study scarcely show uranium-induced behavioral effects at the oral doses of UAD here administered, these effects, as well as the slight influence of restraint stress noted in some tests can not be underrated.

Paper presented at Measuring Behavior 2005 , 5^th International Conference on Methods and Techniques in Behavioral Research, 30 August - 2 September 2005, Wageningen, The Netherlands.

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