Figure 2. Experiment 1: Ketamine Sensitization at Low Doses.
(a) Timecourse of response to ketamine (5.0, 10.0 and 20.0 mg/kg) on Day 1 of treatment (ambulations). *=20 mg/kg different from saline. (b) Timecourse of response to ketamine on Day 5 of treatment (ambulations). Note the increases in response compared to Day 1. *=20 mg/kg different from saline. **=10 and 20 mg/kg different from saline. (c) Total activity across days of treatment (ambulations). *=20 mg/kg different from response on day 1. (d) Total activity across days of treatment (fine movements). *=20 mg/kg different from response on day 1. **=10 and 20 mg/kg different from response on day 1. ***=5, 10 and 20 mg/kg different from response on day 1. Although 20 mg/kg was the only dose that showed a significant increase in locomotion on Day 1, there was evidence of sensitization at all three doses.