 In at least certain cell types, however, TPα also stimulates cells by activating the Gs family of G proteins while TPβ also stimulates cells by activating the Gi class of G proteins.This leads to the stimulation or inhibition, respectively, of adenylate cyclase activity and thereby very different cellular responses.Differences in their C-terminal tail sequence also allow for significant differences in the two receptors internalization and thereby desensitization (i.e.