Fig. 4.
Schematic illustration of a) Effect of the main 5-HT receptors classes on β-cell proliferation, b) Effect of 5-HTR1F on glucagon in α-cell, and c) The relationship between the reduction and augmentation of insulin release depending on [5-HT]e and [5-HT]i. Abbreviations: 5-HTi, 5-Hydroxytryptophan intracellular; 5-HTe, 5-Hydroxytryptophan extracellular; SERT, 5-HT Transporter; cAMP, Cyclic Adenosine Monophosphate; GDP, Guanosine diphosphate; GTP, Guanosine 5'-Triphosphate; T Gase, Transglutaminase; TPH1, Tryptophan Hydroxylase 1; 5HTR2B, 5-Hydroxytryptamine receptor 2B; 5HTR3, 5-Hydroxytryptamine Receptor 3; 5-HTR1D, 5-Hydroxytryptamine Receptor 1D; AC, adenylate cyclase; Gi, inhibitory G protein