In mice, the team looked at how tirzepatide works in the brain, in what they note as “a combination of neuroanatomical approaches.” The drug held a faint fluorescent tag and was tracked over exposed parts of the brain with iDISCO light sheet method. From there, they noted shifts in neuronal activity in different regions of the brain with whole-brain FOS analysis, while RNAscope showed where the GlP1r and Gipr receptors are. With genetic tools, they switched certain neurons on and off, and together with feeding work, linked those brain sites to appetite and weight.