title: Eating high fat chow decreases dopamine clearance in adolescent and adult male rats but selectively enhances the locomotor stimulating effects of cocaine in adolescents.
abstract: BACKGROUND
  Feeding conditions can influence dopamine neurotransmission and impact behavioral and neurochemical effects of drugs acting on dopamine systems. This study examined whether eating high fat chow alters the locomotor effects of cocaine and dopamine transporter activity in adolescent (postnatal day 25) and adult (postnatal day 75) male Sprague-Dawley rats.
  
  
  METHODS
  Dose-response curves for cocaine-induced locomotor activity were generated in rats with free access to either standard or high fat chow or restricted access to high fat chow (body weight matched to rats eating standard chow).
  
  
  RESULTS
  Compared with eating standard chow, eating high fat chow increased the sensitivity of adolescent, but not adult, rats to the acute effects of cocaine. When tested once per week, sensitization to the locomotor effects of cocaine was enhanced in adolescent rats eating high fat chow compared with adolescent rats eating standard chow. Sensitization to cocaine was not different among feeding conditions in adults. When adolescent rats that previously ate high fat chow ate standard chow, sensitivity to cocaine returned to normal. As measured by chronoamperometry, dopamine clearance rate in striatum was decreased in both adolescent and adult rats eating high fat chow compared with age-matched rats eating standard chow.
  
  
  CONCLUSIONS
  These results suggest that high fat diet-induced reductions in dopamine clearance rate do not always correspond to increased sensitivity to the locomotor effects of cocaine, suggesting that mechanisms other than dopamine transporter might play a role. Moreover, in adolescent but not adult rats, eating high fat chow increases sensitivity to cocaine and enhances the sensitization that develops to cocaine.
authors: Departments of Pharmacology (Drs Baladi, Daws, and France), Psychiatry (Dr France), and Physiology (Ms. Horton, Mr. Owens, and Dr. Daws), University of Texas Health Science Center at San Antonio, San Antonio, Texas.
authors: Michelle G
authors: MG
authors: Baladi
authors: Departments of Pharmacology (Drs Baladi, Daws, and France), Psychiatry (Dr France), and Physiology (Ms. Horton, Mr. Owens, and Dr. Daws), University of Texas Health Science Center at San Antonio, San Antonio, Texas.
authors: Rebecca E
authors: RE
authors: Horton
authors: Departments of Pharmacology (Drs Baladi, Daws, and France), Psychiatry (Dr France), and Physiology (Ms. Horton, Mr. Owens, and Dr. Daws), University of Texas Health Science Center at San Antonio, San Antonio, Texas.
authors: William A
authors: WA
authors: Owens
authors: Departments of Pharmacology (Drs Baladi, Daws, and France), Psychiatry (Dr France), and Physiology (Ms. Horton, Mr. Owens, and Dr. Daws), University of Texas Health Science Center at San Antonio, San Antonio, Texas.
authors: Lynette C
authors: LC
authors: Daws
authors: Departments of Pharmacology (Drs Baladi, Daws, and France), Psychiatry (Dr France), and Physiology (Ms. Horton, Mr. Owens, and Dr. Daws), University of Texas Health Science Center at San Antonio, San Antonio, Texas france@uthscsa.edu.
authors: Charles P
authors: CP
authors: France
mesh_terms: D000375:Aging / Q000378:metabolism / Q000523:psychology*; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D001835:Body Weight / Q000187:drug effects; D003042:Cocaine / Q000008:administration & dosage / Q000494:pharmacology*; D059305:Diet, High-Fat / Q000379:methods; D004298:Dopamine / Q000378:metabolism*; D018765:Dopamine Uptake Inhibitors / Q000008:administration & dosage / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004435:Eating / Q000187:drug effects / Q000523:psychology*; D008124:Locomotion / Q000187:drug effects*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D066328:Ventral Striatum / Q000187:drug effects / Q000378:metabolism
chemical_list: D018765:Dopamine Uptake Inhibitors; D003042:Cocaine; D004298:Dopamine
keywords: Cocaine; adolescents; dopamine transporter; high fat chow; locomotor activity