1. Adolescent Oxycodone Exposure’s Impact on Drug Sensitivity in Adulthood Department of Psychology, Bridgewater College, Bridgewater, Virginia BRICE, A.C., HENLINE, J.N., JOHNSON, D.J., MORGAN, M., SHEFFER, C.T., STUDTMANN, C.E.
Weeks
1-5
6-8 8 9
Activity
Injections
Recovery Period
Rotarod training
Rotarod testing
Results
Introduction Opioid abuse is on the rise amongst our nation’s youth. Further, opioids are becoming increasingly available and prescribed (National Institute on Drug Abuse, 2014). In 2014, 467,000 adolescents reported to be nonmedical users of prescription pain pills, with 168,000 having an addiction (American Society of Addiction Medicine, 2016). Adolescent drug use is extremely concerning due to the fact that adolescence is a period of development which is extremely vulnerable to the damaging impact drugs have on the brain (Kelley, Perry, Hershey, & Baird, 2010). With substance abuse on the rise amongst this age group, it is important to understand the repercussions, particularly with respect to the impact on sensitivity to drugs in adulthood. A decreased sensitivity to drugs in adulthood places subjects at a greater risk for substance abuse problems and may be a contributing factor in perpetuation of drug use. Method male adolescent C57BL/6J mice were housed individually with access to food and water in light (12:12 h light/ dark cycle, lights on at 0700 hours). Upon arrival, they received a 2 day acclimation period. 2. Mice were split into four groups to receive OxyContin. Each mouse was given intraperitoneal injections with either a low dose of 1.25 mg/kg, with the other three groups given a medium dose of 2.5 mg/kg, high dose of 5.0 mg/kg, and a dose of saline. tested with ol. Mice were trained for 5 days on the Rotorod motor apparatus. 7. Mice were given saline in the first testing day and either alcohol or cocaine for 5 days following. 8. During testing, mice received an increase in dose every day. With cocaine doses beginning at 1.25 mg/ml, then 2.5 mg/mL, 5.0 mg/mL, 10.0 mg/mL, and 20.0 mg/mL. Alcohol groups followed the same premise with doses of % alc/vol, 6% alc/vol, 9% alc/vol, 12% alc/vol, and 15% alc/vol.
Fig. 2 (c & d). A. Cocaine Rotarod Percent Change. The Low oxycodone group performed better on the rotarod at very low to high doses. Every group performed the same at a very high dose and stayed on the Rotarod for the longest amount of time on this dose. B. Performed better as cocaine increased. There was a change in sensitivity but less so than alcohol.
Fig. 4(a & b). A. Alcohol Percent Change. Shows the percent change from saline to each alcohol dose. High oxycodone group was less sensitive to low to medium alcohol doses on the rotarod compared to the low oxycodone group and saline group. The low oxycodone group spent more time on the rotarod when exposed to alcohol than compared to the saline group. B. As the dose is increasing the mice are still developing tolerance, lowering their sensitivity to the drug.
Conclusion
Oxycodone exposure in adolescence impacts sensitivity to other drugs in adulthood. The high oxycodone group did not begin to show balance and coordination deficits until they were given a high dose of alcohol. All dose groups’ times significantly dropped when given a very high dose of alcohol. When the mice were given cocaine instead of alcohol the low dose oxycodone group performed best at all doses except the very high dose when they all performed the same. This shows that when exposed to opioids in adolescence they will have decreased sensitivity to drugs in adulthood meaning a higher dose is needed to feel the effects of drugs.
Literature Cited
National Institute on Drug Abuse (NIDA). (2014, May 14). America's Addiction to
Opioids: Heroin and Prescription Drug Abuse. Retrieved August 30, 2016
American Society of Addiction Medicine (2016). Opioid Addiction: 2016 Facts andFigures, 1-3. Retrieved April 6, 2016.
Kelley, B. M., Perry, C. E., Hershey, H. E., & Baird, A. L. (2010). Cocaine's impact onaffect, activity, and reward are dose-dependently impacted by age: adolescentversus adult exposure. In Horizons in neuroscience research (4th ed., pp. 2-27). Nova Science Publishers, Inc.