RESEARCH REPORTSEffects of amphetamine on striatal dopamine release, open-field activity, and play in Fischer 344 and Sprague–Dawley ratsSiviy, Stephen M.a; McDowell, Lana S.a; Eck, Samantha R.a; Turano, Alexandraa; Akopian, Garnikb; Walsh, John P.b Author Information aDepartment of Psychology, Gettysburg College, Gettysburg, Pennsylvania bDavis School of Gerontology, University of Southern California, Los Angeles, California, USA Correspondence to Stephen M. Siviy, PhD, Department of Psychology, Gettysburg College, 300 North Washington Street, Gettysburg, PA 17325, USA E-mail: [email protected] Received March 12, 2015 Accepted August 20, 2015 Behavioural Pharmacology: December 2015 - Volume 26 - Issue 8 Special Issue Pharmacological Approaches To The Study Of Social Behaviour - Part 3: Drug Effects O - p 720-732 doi: 10.1097/FBP.0000000000000191 Buy Metrics Abstract Previous work from our laboratories has shown that juvenile Fischer 344 (F344) rats are less playful than other strains and also appear to be compromised in dopamine (DA) functioning. To determine whether the dysfunctional play in this strain is associated with deficits in the handling and delivery of vesicular DA, the following experiments assessed the extent to which F344 rats are differentially sensitive to the effects of amphetamine. When exposed to amphetamine, striatal slices obtained from F344 rats showed a small increase in unstimulated DA release when compared with slices from Sprague–Dawley rats; they also showed a more rapid high K+-mediated release of DA. These data provide tentative support for the hypothesis that F344 rats have a higher concentration of cytoplasmic DA than Sprague–Dawley rats. When rats were tested for activity in an open field, F344 rats presented a pattern of results that was consistent with either an enhanced response to amphetamine (3 mg/kg) or a more rapid release of DA (10 mg/kg). Although there was some indication that amphetamine had a dose-dependent differential effect on play in the two strains, play in F344 rats was not enhanced to any degree by amphetamine. Although these results are not consistent with our working hypothesis that F344 rats are less playful because of a deficit in vesicular release of DA, they still suggest that this strain may be a useful model for better understanding the role of DA in social behavior during the juvenile period. Copyright © 2015 YEAR Wolters Kluwer Health, Inc. All rights reserved.