Fig. 8.

The effect of WIN55,212-2 on average swimming velocity upon repeated dark challenges. The response to repeated dark challenges did not significantly change in vehicle-treated larvae. WIN55,212-2 (2 μM) abolished the response to the first two dark challenges, but a reduced effect of this Cnr1 agonist was observed on the response to the third, fourth, and fifth dark challenges, indicating receptor desensitization. Group sizes are reported in parentheses. Data shown are means ± SEM. A significant difference compared to the first dark challenge is indicated. ****P ≤ 0.0001