TY  - JOUR
PY  - 2015//
TI  - Effects of acute and repeated dosing of the synthetic cannabinoid CP55,940 on intracranial self-stimulation in mice
JO  - Drug and alcohol dependence
A1  - Grim, Travis W.
A1  - Wiebelhaus, Jason M.
A1  - Morales, Anthony J.
A1  - Negus, S. Stevens
A1  - Lichtman, Aron H.
SP  - 31
EP  - 37
VL  - 150
IS  - 
N2  - BACKGROUND: Synthetic cannabinoids have emerged as a significant public health concern. To increase the knowledge of how these molecules interact on brain reward processes, we investigated the effects of CP55,940, a high efficacy synthetic CB1 receptor agonist, in a frequency-rate intracranial self-stimulation (ICSS) procedure. <br><br>METHODS: The impact of acute and repeated administration (seven days) of CP55,940 on operant responding for electrical brain stimulation of the medial forebrain bundle was investigated in C57BL/6J mice. <br><br>RESULTS: CP55,940 attenuated ICSS in a dose-related fashion (ED50 (95% C.L.)=0.15 (0.12-0.18)mg/kg). This effect was blocked by the CB1 receptor antagonist rimonabant. Tolerance developed quickly, though not completely, to the rate-decreasing effects of CP55,940 (0.3mg/kg). Abrupt discontinuation of drug did not alter baseline responding for up to seven days. Moreover, rimonabant (10mg/kg) challenge did not alter ICSS responding in mice treated repeatedly with CP55,940. <br><br>CONCLUSIONS: The finding that CP55,940 reduced ICSS in mice with no evidence of facilitation at any dose is consistent with synthetic cannabinoid effects on ICSS in rats. CP55,940-induced ICSS depression was mediated through a CB1 receptor mechanism. Additionally, tolerance and dependence following repeated CP55,940 administration were dissociable. Thus, CP55,940 does not produce reward-like effects in ICSS under these conditions.<p />  <p>Language: en</p>
LA  - en
SN  - 0376-8716
UR  - http://dx.doi.org/10.1016/j.drugalcdep.2015.01.022
ID  - ref1
ER  -