EFFECTS OF CENTRALLY ACTING DRUGS ON EXPLORATORY BEHAVIOUR IN RATS

Abstract

Steinberg and her colleagues have investigated the effects of amphetamine, amylobarbitone and of mixtures of these two drugs on the exploratory activity of rats placed into a symmetrical Y-shaped box. They found that some of the drug mixtures produced great increases in exploratory activity, although alone each substance produced little or no increase. When a mixture of amphetamine and amylobarbitone was given to rats which had had repeated, or even a single exposure to the Y-box beforehand, there was no increase in exploration (Steinberg, Rushton & Tinson, 1961; Rushton & Steinberg, 1963; Rushton, Steinberg & Tinson, 1963). A possible interpretation of these results is that some mixtures of amphetamine and amylobarbitone may lead to increased exploratory activity by reducing the susceptibility of rats to environmental stimuli; this would not be inconsistent with the clinical use of such drug combinations in anxiety states. It was decided that the Y-box offered an interesting approach to the study of centrally acting drugs. In the present investigation the actions of several such drugs on the exploratory activity of rats placed into this environment have been investigated.