Interaction of chronic food restriction and methylphenidate in sensation seeking of rats.
| Publication Type | Academic Article |
| Authors | Talishinsky A, Nicolas C, Ikemoto S |
| Journal | Psychopharmacology (Berl) |
| Volume | 234 |
| Issue | 14 |
| Pagination | 2197-2206 |
| Date Published | 04/08/2017 |
| ISSN | 1432-2072 |
| Keywords | Body Weight, Central Nervous System Stimulants, Methylphenidate |
| Abstract | RATIONALE: It is necessary to understand better how chronic food restriction (CFR) and psychostimulant drugs interact in motivated behavior unrelated to food or energy homeostasis. OBJECTIVES: We examined whether CFR augments methylphenidate (MPH)-potentiated responding reinforced by visual sensation (VS) and whether repeated MPH injections or prolonged CFR further augments such responses. METHODS: Before starting the following experiments, rats on a CFR diet received a limited daily ration in such a way that their body weights decreased to 85-90% of their original weights over 2 weeks. In experiment 1, rats on CFR and ad libitum diet received four injections of varying MPH doses (0, 2.5, 5, and 10 mg/kg). In experiment 2, CFR and ad libitum groups received repeated injections of MPH (2.5 mg/kg). In experiment 3, half of CFR rats received repeated injections of MPH (2.5 mg/kg), and the other half received saline, and following a 7-day abstinence, they all received the 2.5-mg/kg dose of MPH. RESULTS: CFR rats increased VS-reinforced responding more than ad libitum rats when they received MPH. Repeated injections of MPH with prolonged CFR further increased VS-reinforced responding. We found a double dissociation where prolonged CFR (3 vs. 6 weeks) made VS-reinforced responding, but not locomotor activity, more responsive to MPH, whereas repeated MPH injections made locomotor activity, but not VS-reinforced responding, more responsive to MPH. CONCLUSIONS: CFR markedly potentiates effects of MPH on VS-reinforced responding. The present study demonstrates that the longer CFR continues, the greater psychostimulant drugs augment behavioral interaction with salient stimuli. |
| DOI | 10.1007/s00213-017-4625-6 |
| PubMed ID | 28391507 |
| PubMed Central ID | PMC5482769 |