(a) Mouse head twitch response (HTR) comparison of psychedelic (rac)-DOPR and non-psychedelic (rac)-Ariadne and its enantiomers (15 min period). (b) Time course of HTR events in vehicle, DOPR and (R)-Ariadne treated mice. Green band shows the 15-min. time period used for HTR scoring for dose-response studies. (c) Brain and plasma pharmacokinetic evaluation of Ariadne. Green band shows the time period used for HTR scoring for dose-response studies. N = 3 per time point. (d) HTR dose-response curves for DOPR, Ariadne and its analogs (15 min.). The same data for DOPR and Ariadne as in panel b, shown here for clarity of comparison. (e) Effect of 5-HT2A receptor antagonist MDL100907 (0.01 and 0.032 mg/kg, ip, 15 min prior) on (R)-Ariadne (10 mg/kg, sc) induced HTR (n = 5/group). The pre-treated mice exhibit comparable HTR counts to vehicle-treated mice. (f) Mouse 5-HT2A Gq-BRET dissociation assay for serotonin, DOPR, (R)-Ariadne and 4C-TFM. (g) Mouse open-field assay for evaluation of (R)-Ariadne’s effect on novelty induced locomotion, n=8/group, administered subcutaneously. (h) Mouse open-field assay for DOPR, n=8/group, administered subcutaneously. One-way ANOVA (E) with post-hoc Tukey’s test. All values represented as mean ± S.E.M, ****p < 0.0001. For a-d, n = 5/group, HTR behavior was assessed for 15 minutes (t = 5 to t = 20 minutes post subcutaneous injection).