In vitro, functional activity of lorcaserin, DOI, and 5-HT at human (h) and mouse (m) 5-HT2ARs (A and B) and 5-HT2CRs (C and D). All compounds were tested in parallel measuring inositol phosphate production. Data are concentration–response curves showing means and SEMs from a minimum of three, independent experiments. Eleven concentrations of lorcaserin, in half log-increments, were tested in triplicates, and six concentrations of 5-HT and DOI (controls), in log increments, were tested in duplicates. NC is an abbreviation for “no compound,” and the associated data points represent basal receptor activity.