[Ca2+]i modulation of Cl- content controls cell volume in single salivary acinar cells during fluid secretion.
Differential interference contrast microscopy and low-light-level digital imaging of the fluorescent chloride indicator dye 6-methyl-1-(3-sulfonatopropyl)quinolinium (SPQ) were performed simultaneously in single mammalian salivary gland acinar cells to examine the relationship between cytoplasmic chloride concentration [( Cl-]i) and cell volume during stimulus-secretion coupling. Agonist stimulation of Cl(-)-driven fluid secretion is associated with rapid, Ca2(+)-dependent changes of cell volume, which are temporally coupled to changes of [Cl-]i. The agonist-induced changes in [Cl-]i, if accompanied by cations and water, quantitatively account for the cell volume changes, demonstrating in a single cell that cell volume is determined by cell solute content. Agonist-induced modulation of cell volume appears to be a consequence of the requirement to develop appropriate ion gradients necessary for vectorial salt (and fluid) transport.
Foskett
J K
JK
Division of Cell Biology, Hospital for Sick Children, Toronto, Ontario, Canada.
D000818:Animals; D002118:Calcium / Q000494:pharmacology / Q000502:physiology*; D002217:Carbachol / Q000494:pharmacology; D002712:Chlorides / Q000378:metabolism*; D005456:Fluorescent Dyes; D066298:In Vitro Techniques; D007700:Kinetics; D009550:Nigericin / Q000494:pharmacology; D010306:Parotid Gland / Q000166:cytology / Q000187:drug effects / Q000502:physiology* / Q000648:ultrastructure; D011188:Potassium / Q000494:pharmacology; D011806:Quinolinium Compounds; D051381:Rats; D011919:Rats, Inbred Strains; D012463:Saliva / Q000378:metabolism*; D014220:Trialkyltin Compounds / Q000494:pharmacology
D002712:Chlorides; D005456:Fluorescent Dyes; D011806:Quinolinium Compounds; D014220:Trialkyltin Compounds; C011559:tributyltin; C052335:6-methoxy-N-(3-sulfopropyl)quinolinium; D002217:Carbachol; D009550:Nigericin; D011188:Potassium; D002118:Calcium