2.2. Study Design
JWH-018 administered 0.5 mg/kg or 5 mg/kg because Banister and colleagues reported that JWH-018 caused hypothermia and deceleration of heart rate between 0.3-10 mg/kg in rats (24). The study protocol was approved by Inonu University Faculty of Medicine Experimental Animals Ethics Committee with the decision of the ethics committee numbered 2015/A-24. A scientific study permit (No: 21589509/279) was obtained from the Ministry of Justice on March 04, 2015. In the experiments, fifty Wistar albino rats weighing 343-429 g which were obtained from the Inonu University Experimental Animal Research Center. Rats were maintained in standard cages (12 hours of daylight, 12 hours of darkness, in ventilated (humidity 60 ± 5%), constant temperature (21±2°C) rooms) and in special cages. Eight mm standard rat pellet diet was used in the feeding process. Randomization was utilized to allocate animals to different rat groups, collect and process data, and analyze the results with investigators who were blind to the treatment groups. This animal experimental study was designed to ARRIVE guidelines (25). To eliminate bias in the way the experiment was conducted, a simple randomization procedure was utilized to assign the rats to the groups. Fifty rats were randomly divided into five groups (n=10 for each group) as follows:
1. Control group (C1-10): Rats were treated with vehicle solution (2 ml of saline containing 2.5% tween 80 and 5% ethanol) intraperitoneally (i.p.) for 14 days.
2. Acute low-dose group (ALD1-10): Rats were treated with 0.5 mg/kg JWH-018 i.p. for 1 day.
3. Acute high-dose group (AHD1-10): Rats were treated with 5 mg/kg JWH-018 i.p. for 1 day.
4. Subacute low-dose group (SALD1-10): Rats were treated with 0.5 mg/kg JWH-018 i.p. for 14 days.
5. Subacute high-dose group (SAHD1-10): Rats were treated with 5 mg/kg JWH-018 i.p. for 14 days.