Presentation Title
Effect of Kappa Opioid Receptor Blockade on Methamphetamine-Induced Reward and Aversion
Faculty Mentor
Dr. Keith Trujillo
Start Date
18-11-2017 12:30 PM
End Date
18-11-2017 1:30 PM
Location
BSC-Ursa Minor 23
Session
Poster 2
Type of Presentation
Poster
Subject Area
behavioral_social_sciences
Abstract
Methamphetamine (METH) is a potent and highly abused psychomotor stimulant that produces powerful rewarding effects. Most of the scientific literature examining the neural mechanisms of METH have focused on the effect of this drug on the neurotransmitter dopamine. However, recent findings suggest that endogenous opioids are also affected by psychomotor stimulants such as METH, and that activation of these neurotransmitters may contribute to the rewarding and aversive effects induced by this drug. The current study is aimed at investigating the potential role of kappa opioid receptor activation in the response to METH in laboratory rats. METH was administered in the presence or absence of norbinaltorphimine (nor-BNI), a kappa opioid receptor antagonist, and locomotor activity and ultrasonic vocalizations (USVs) were assessed. In a pilot study, nor-BNI (5.0 mg/kg) increased METH-induced (3.0 mg/kg) 50 kHz USVs and locomotor activity, which is consistent with our hypothesis. We are currently replicating and expanding this research, examining the effect of nor-BNI on the response to METH (1.0 or 3.0 mg/kg). We hypothesize that nor-BNI will increase METH-induced 50 kHz USVs, reflecting increased rewarding effects of METH, and will decrease METH-induced 22 kHz USVs, reflecting decreased aversive effects of METH. Also, we hypothesize that nor-BNI will increase METH-induced locomotor activity in a manner parallel to 50 kHz USVs. USVs were assessed with Avisoft 416H recording device and locomotor behavior was assessed with a Kinder Scientific Motor Monitor. The treatment groups included: saline (placebo); nor-BNI (5.0 mg/kg); METH (1.0 or 3.0 mg/kg); and nor-BNI+METH.
Key words: kappa receptors, laboratory rats, locomotor behavior, methamphetamine, opioid antagonist, ultrasonic vocalizations
Effect of Kappa Opioid Receptor Blockade on Methamphetamine-Induced Reward and Aversion
BSC-Ursa Minor 23
Methamphetamine (METH) is a potent and highly abused psychomotor stimulant that produces powerful rewarding effects. Most of the scientific literature examining the neural mechanisms of METH have focused on the effect of this drug on the neurotransmitter dopamine. However, recent findings suggest that endogenous opioids are also affected by psychomotor stimulants such as METH, and that activation of these neurotransmitters may contribute to the rewarding and aversive effects induced by this drug. The current study is aimed at investigating the potential role of kappa opioid receptor activation in the response to METH in laboratory rats. METH was administered in the presence or absence of norbinaltorphimine (nor-BNI), a kappa opioid receptor antagonist, and locomotor activity and ultrasonic vocalizations (USVs) were assessed. In a pilot study, nor-BNI (5.0 mg/kg) increased METH-induced (3.0 mg/kg) 50 kHz USVs and locomotor activity, which is consistent with our hypothesis. We are currently replicating and expanding this research, examining the effect of nor-BNI on the response to METH (1.0 or 3.0 mg/kg). We hypothesize that nor-BNI will increase METH-induced 50 kHz USVs, reflecting increased rewarding effects of METH, and will decrease METH-induced 22 kHz USVs, reflecting decreased aversive effects of METH. Also, we hypothesize that nor-BNI will increase METH-induced locomotor activity in a manner parallel to 50 kHz USVs. USVs were assessed with Avisoft 416H recording device and locomotor behavior was assessed with a Kinder Scientific Motor Monitor. The treatment groups included: saline (placebo); nor-BNI (5.0 mg/kg); METH (1.0 or 3.0 mg/kg); and nor-BNI+METH.
Key words: kappa receptors, laboratory rats, locomotor behavior, methamphetamine, opioid antagonist, ultrasonic vocalizations