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Joseph Schroeder

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Pain is a common ailment that affects a large number of people around the world. However, there is limited research investigating external factors (such as stress and enrichment) that impact pain and the effectiveness of analgesics. This study examined the relationship between enrichment environments and acute stress on pain sensitivity and the effects of four analgesics (lidocaine, ibuprofen, pregabalin, and morphine). To measure analgesic effect, a standard tail-flick apparatus was used. Thirty-seven Sprague-Dawley rats were raised in one of three enrichment environments (impoverished, standard, or enriched). Every rat received all analgesics twice (once with no stress and once with an acute stressor in the form of fox scent exposure). Tail flick measurements (on which ANOVA and t-test analyses were conducted) were taken after analgesic administration. Morphine was shown to produce the strongest analgesic effect (p < .0001); however, the hypothesis that enrichment would be positively correlated with analgesic effect was not supported overall; and no conclusive results were determined regarding the impact of stress on analgesic effect. Future research can further investigate these variables and their impact on effective pain management and analgesic administration.



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