The Effects of Chronic Lysergic Acid Diethylamide Exposure and Withdrawal in Zebrafish

Zebrafish (Danio rerio) have recently emerged as an excellent model for neuropharmacological research due to the similarities in neurochemistry they share with humans. This similarity enables researchers to generalize findings concerning the relationship between neurotransmitter systems and hallucinogenic drugs to humans. The purpose of the current study was to investigate the behavioural effects of chronic lysergic acid diethylamide (LSD) exposure and withdrawal in zebrafish. Subjects were randomly assigned to a low or high dose of either 100 μg/L or 250 μg/L for 10 days. Behaviour in the open field test was assessed on the 10th day for chronic exposure and on the 11th  day for withdrawal. The present study hypothesized a dose-dependent anxiolytic effect of chronic exposure, similar to what was found in past research for acute exposure. It was also predicted that a withdrawal response of treated fish would be demonstrated with heightened anxiety. Results indicated that neither chronic exposure to nor withdrawal from LSD affected swimming speed or distance moved; thus, implying that LSD did not affect motor control. However, results for chronic exposure revealed no significant increase in behaviours indicative of low anxiety.  Evidence seemed to suggest a tolerance combined with a lack of withdrawal with treated fish performing similar to controls in each round of testing. Future research should address the acute application of LSD in panic disorder treatment and differing drug exposure intervals with repeated testing. Department: Psychology Faculty Mentor: Dr. Melike Schalomo