title: Differential effects of aprepitant, a clinically used neurokinin-1 receptor antagonist on the expression of conditioned psychostimulant versus opioid reward.
abstract: Neurokinin-1 receptor (NK1R) signaling modulates behaviors associated with psychostimulants and opioids. Psychostimulants, such as amphetamine (AMPH) and cocaine, bind to monoamine transporters and alter their functions. Both dopamine and norepinephrine transporters are regulated by NK1R activation suggesting a role for NK1R mediated catecholamine transporter regulation in psychostimulant-mediated behaviors.
  
  
  
  The effect of in vivo administration of aprepitant (10 mg/kg) on the expression of AMPH (0.5 and 2 mg/kg) and cocaine (5 and 20 mg/kg)-induced conditioned place preference (CPP) as well as locomotor activation was examined in C57BL/6J mice. The effect of aprepitant on morphine (1 and 5 mg/kg)-induced CPP was also examined to identify the specific actions of aprepitant on psychostimulant versus opioid-induced behaviors.
  
  
  
  Aprepitant administration significantly attenuated the CPP expression and locomotor activation produced by AMPH and cocaine. In contrast, aprepitant significantly enhanced the expression of CPP produced by morphine while significantly suppressing the locomotor activity of the mice conditioned with morphine. Aprepitant by itself did not induce significant CPP or conditioned place aversion or locomotor activation or suppression.
  
  
  
  Attenuation of AMPH or cocaine-induced CPP and locomotor activation by aprepitant suggests a role for NK1R signaling in psychostimulant-mediated behaviors. Stimulation of morphine-induced CPP expression and suppression of locomotor activity of morphine-conditioned mice suggest differential effects of NK1R antagonism on conditioned psychostimulant versus opioid reward. Collectively, these findings indicate that clinically used NK1R antagonist, aprepitant may serve as a potential therapeutic agent in the treatment of psychostimulant abuse.
authors.affiliation: Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA, 23298, USA.
authors.forename: Padmanabhan
authors.initials: P
authors.lastname: Mannangatti
authors.affiliation: Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA, 23298, USA.
authors.forename: Santhanalakshmi
authors.initials: S
authors.lastname: Sundaramurthy
authors.affiliation: Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA, 23298, USA.
authors.forename: Sammanda
authors.initials: S
authors.lastname: Ramamoorthy
authors.affiliation: Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA, 23298, USA. lankupalle.jayanthi@vcuhealth.org.
authors.forename: Lankupalle D
authors.initials: LD
authors.lastname: Jayanthi
mesh_terms: D000661:Amphetamine / Q000494:pharmacology; D000701:Analgesics, Opioid / Q000494:pharmacology*; D000818:Animals; D000077608:Aprepitant; D001245:Association Learning / Q000187:drug effects; D000697:Central Nervous System Stimulants / Q000494:pharmacology*; D003042:Cocaine / Q000494:pharmacology; D003213:Conditioning, Psychological / Q000187:drug effects*; D008124:Locomotion / Q000187:drug effects; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009020:Morphine / Q000494:pharmacology; D009025:Morpholines / Q000494:pharmacology*; D009043:Motor Activity / Q000187:drug effects; D064729:Neurokinin-1 Receptor Antagonists / Q000494:pharmacology*; D012201:Reward
chemical_list: D000701:Analgesics, Opioid; D000697:Central Nervous System Stimulants; D009025:Morpholines; D064729:Neurokinin-1 Receptor Antagonists; D000077608:Aprepitant; D009020:Morphine; D000661:Amphetamine; D003042:Cocaine
keywords: Amphetamine; Antagonist; Aprepitant; Cocaine; Conditioned place preference; Drug abuse; Morphine; Neurokinin-1 receptor; Opioids; Psychostimulants