In agreement with previous reports which show that activation of the 5-HT4d receptor induces APP shedding in CHO cells [7], we find a significant upregulation of SEAP (secreted alkaline phosphatase) activity in SH-SY5Y human neuroblastoma cells transiently transfected with human 5-HT4d (pcDNA3.1-5-HT4d) and human wild type APP695 coupled to SEAP (pEAK12-AP-APP) following treatment with the 5-HT4 receptor agonists prucalopride or 5-HT. Here, APP is linked to neuroblastoma.