Behavioural responses to elevated plus-maze and defensive burying testing:Effects on subsequent ethanol intake and effect of ethanol on retention ofthe burying response

Based upon repeated observations of a relationship between defensive buryin g (DB), ethanol intake and stress ulcer susceptibility, and recurring quest ions regarding what DB behaviour reflects, two experiments were performed. Experiment 1 showed that prod shock exposure per se reduced subsequent etha nol intake, as did access to burying material. In rats without burying mate rial in the conditioning phase, subsequent access to ethanol resulted in re duced DB activity in the retest, pointing to some interference by ethanol o n latent learning. Experiment 2 showed that there were no effects of anxiet y as measured in the elevated plus-maze (EPM) on saccharin or ethanol intak e. Behaviours in the EPM and DB test did not correlate. Rats entering the o pen arm on first entry into the EPM drank and preferred more ethanol than t hose choosing the closed arm. Saccharin intake was negatively related to bu rying latency, and positively related to initial ethanol intake. In conclus ion, it is still questionable whether the DB test is measuring anxiety, but exposure to the test or performance of the DB activity appears to cause mo difications, psychologically and perhaps physiologically, in rats. Ethanol intake may under certain conditions interfere with the acquisition of a def ensive response. The testing of DB behaviour may be useful in studying drug effects on latent learning of prepared responses.