The researchers also investigated how differences in binding affected chemical cascades. They triggered both 1B and 2B with the powerful psychedelic drug LSD and one of its precursors, a migraine drug called ergotamine. The drugs produced two different chemical cascades — G-protein and β-arrestin — from the 1B receptor, but only one (β-arrestin) from the 2B receptor.
Roth says that learning to control the cascades is likely to be crucial in maximizing beneficial effects of drugs and minimizing side effects. “In some cases G-protein signaling is good; arrestin is bad. In other systems, vice versa,” he says.
However, Anacker points out that serotonin receptors can have different effects depending on where in the brain they are located and other factors. “It would be too simple to say one cascade is beneficial and the other not,” he says.