Figure 1: The two salivary secretory pathways: protein exocytosis and fluid secretion. Salivary secretion is modulated by the autonomous system: the sympathetic system activates the adenylate cyclase increasing the level of cAMP leading to the secretion of proteins from the secretory granules. The parasympathetic, instead, by the upmodulation of phospholipase C causes the raising of intracellular Ca2+ and fluid secretion. BEST2: bestrophin 2. AQP5: aquaporin 5. VAMP: vesicle associated membrane protein. CALM: calmodulin like 6. CD38/157: bone marrow stromal cell antigen 1. PKG: protein kinase, cGMP-dependent, type I. GC-s: guanylate cyclase 1 soluble subunit alpha 2. NOS: nitric oxide synthase 1. RYR: ryanodine receptor 3. IP3r: inositol 1,4,5-trisphosphate receptor type 1. Cat-like: transient receptor potential cation channel subfamily V member 6. NHE1: solute carrier family 9 member A1. MaxiK: potassium large conductance calcium-activated channel subfamily M alpha member 1. KCNN4: potassium intermediate/small conductance calcium-activated channel subfamily N member 4. NKCC1: solute carrier family 12 member 2. PMCA: ATPase plasma membrane Ca2+ transporting 1. ATP: ATPase Na+/K+ transporting family member beta 4. M3R: cholinergic receptor muscarinic 3. α1R: adrenoceptor α 1D. AC: adenylate cyclase 1. βR: adrenoceptor beta 1. Gs: guanine nucleotide-binding protein G(s) subunit α. Gq: guanine nucleotide-binding protein G(q) subunit α. PLCβ: phospholipase C β 1. MUC5B: mucin 5B, oligomeric mucus/gel-forming. MUC7: mucin 7, secreted. AMY1: amylase, alpha 1A. aPRP: proline rich protein HaeIII subfamily 1. bPRP: proline rich protein BstNI subfamily 1. DMBT1: deleted in malignant brain tumors 1 protein. Cystatin: cystatin-SN. Histatin: histatin 1. Statherin: statherin. LYZ: lysozyme C. LPO: lactoperoxidase. LL-37: cathelicidin antimicrobial peptide. See [1214].