Rachel Aruldas

The use of cocaine, an addictive stimulant, is detrimental and has increased in recent years. Cocaine sensitization, a behavioral phenomenon used to study the effects of repeated cocaine use, reduces phosphorylated AMPK (pAMPK) in the dorsal striatum (DStr). We examined the effect of cocaine sensitization on pAMPK in multiple brain regions. Sprague Dawley rats were given intraperitoneal (IP) injections for six days during the development of sensitization. On the seventh day, rats received a challenge IP injection. The rats were divided into four groups based on the sensitization and challenge injections: cocaine & cocaine (c-c), cocaine & saline (c-s), saline & cocaine (s-c), saline & saline (s-s). The dosage of cocaine was 15mg/kg. The activity of rats was tracked in a locomotor arena for forty-five minutes following daily injections. After recording locomotion on the seventh day, the rats were sacrificed. Tissue from the NAc shell, NAc core, and medial prefrontal cortex (mPFC) were extracted. Tissue from the DStr was also extracted as a positive control. Western Blots were used to quantify total AMPK and pAMPK levels. We hypothesize that group c-c will have the lowest ratio of pAMPK/AMPK, and group s-c will have the highest ratio of pAMPK/AMPK. Locomotion data revealed that the distance traveled by rats significantly increased following cocaine injections, confirming that the rats underwent cocaine sensitization. Tissue from the DStr, NAc, and mPFC have been collected and Western blots are being performed on the tissue. This experiment’s results will help us better understand cocaine’s impact on the brain.