Are salivary glands cell lines in culture a good model for purinergic receptors in salivary glands?

• Published in: Archives of oral biology 1999-05, Vol.44, p.S63-S66
• Main Authors: Carmel, Ziv, Amsallem, Hagai, Métioui, Mourad, Dehaye, Jean-Paul, Moran, Arie
• Format: Article
• Language: English
• Subjects: Adenosine Triphosphate - administration & dosage; Adenosine Triphosphate - pharmacology; Calcium - metabolism; Carbachol - pharmacology; Cell Line; Cells, Cultured; Cholinergic Agonists - pharmacology; Collagen - metabolism; Culture Media; Dentistry; Enzyme Inhibitors - pharmacology; Extracellular Matrix - metabolism; Humans; Inositol Phosphates - biosynthesis; Parotid Gland - cytology; Parotid Gland - drug effects; Parotid Gland - metabolism; Phenotype; Phosphatidylinositols - metabolism; Receptors, Purinergic - drug effects; Receptors, Purinergic - metabolism; Salivary Ducts - cytology; Salivary Ducts - drug effects; Salivary Ducts - metabolism; Signal Transduction - physiology; Space life sciences; Thapsigargin - pharmacology
• ISSN: 0003-9969; 1879-1506
• DOI: 10.1016/S0003-9969(99)90024-9

A major obstacle in studying the physiological and biochemical processes of salivary secretion is the lack of a good ductal cell line model. HSY, an immortalised cell line originating from human parotid gland intercalated ducts, provides a possible model for purinergic, mechanisms in ductal cells. Unlike the biphasic dose response to ATP of isolated submandibular ductal cells, the rise in [Ca2+]i in MY cells shows single Michaelis-Menten kinetics with an apparent K a of 0.8 μM. Pre-incubation with thapsigargin inhibited the ATP induced [Ca 2+] i rise. Both ATP (10 μM) and carbachol (100 μM) increased IP 3 production. Intercalated duct cells may differentiate into acinar or ductal cells in response to appropriate stimuli from extracellular matrix. We therefore attempted to induce a duct-like phenotype in the striated duct-derived HSY cells by growing them on microcarrier beads coated with type I collagen. In Ca-containing medium cells grown on all substrates showed similar responses to ATP. In contrast, in Ca-free medium, [Ca2+]i rose only slightly in cells grown on beads relative to those on glass. This probably resulted from reduced IP 3 Production. Carbachol also induced a much smaller increase in [Ca2+]i and less IP 3 production in cells grown on Cytodex-3. The HSY response to purinergic stimuli by an increase in [Ca 2+] i and IP 3 means that they can be used to study the metabotropic purinergic pathway. The impairment in the HSY responses grown on Cytodex-3 can be used to probe phosposinositol signal transduction in salivary cells.