A rat parotid gland cell line, Par-C10, exhibits neurotransmitter-regulated transepithelial anion secretion

1 Department of Pharmacology, School of Medicine, University of Missouri, Columbia, Missouri 65212; 2 Oral Pathology Research Laboratory, Department of Veterans Affairs Medical Center, Washington, District of Columbia 20422; and 3 Department of Basic Sciences and Oral Research, School of Dentistry, University of Colorado Health Sciences Center, Denver, Colorado 80262 Because of the lack of salivary gland cell lines suitable for Ussing chamber studies, a recently established rat parotid acinar cell line, Par-C10, was grown on permeable supports and evaluated for development of transcellular resistance, polarization, and changes in short-circuit current ( I sc ) in response to relevant receptor agonists. Par-C10 cultures reached confluence in 3-4 days and developed transcellular resistance values of 2,000 · cm 2 . Morphological examination revealed that Par-C10 cells grew as polarized monolayers exhibiting tripartite junctional complexes and the acinar cell-specific characteristic of secretory canaliculi. Par-C10 I sc was increased in response to muscarinic cholinergic and - and -adrenergic agonists on the basolateral aspect of the cultures and to ATP and UTP (through P2Y 2 nucleotide receptors) applied apically. Ion replacement and inhibitor studies indicated that anion secretion was the primary factor in agonist-stimulated I sc . RT-PCR, which confirmed the presence of P2Y 2 nucleotide receptor mRNA in Par-C10 cells, also revealed the presence of mRNA for the cystic fibrosis transmembrane conductance regulator and ClC-2 Cl channel proteins. These findings establish Par-C10 cells as the first cell line of salivary gland origin useful in transcellular ion secretion studies in Ussing chambers. parotid salivary gland; cell culture; Ussing chamber; ion secretion; P2Y 2 receptors; polarized epithelia