title: Continuous measurement of cell volume changes in perfused rat salivary glands by proton NMR.
abstract: Changes in intracellular and extracellular water content have been measured in perfused rat salivary glands by repetitive application of an inversion recovery (IR) pulse sequence. The relaxation reagent Gd-DTPA (10 mM) was included in the perfusate so that the intracellular and extracellular water proton signals could be distinguished by their different longitudinal relaxation times. Changes in water content in response to altered perfusion pressure and perfusate osmolarity were determined at 30-s intervals and indicated a clear separation of the intracellular and extracellular components. Using a modification of the IR pulse sequence, changes in intracellular water content were also measured at 6-s intervals. With this time resolution, differences in the rates of cell shrinkage in response to hyperosmotic perfusates and the secretomotor agonist acetylcholine were observed. The results suggest that this approach offers a relatively noninvasive method for studying cell volume regulation in intact, perfused tissues and organs.
authors.affiliation: School of Biological Sciences, University of Manchester, United Kingdom.
authors.forename: J B
authors.initials: JB
authors.lastname: Larcombe-McDouall
authors.forename: Y
authors.initials: Y
authors.lastname: Seo
authors.forename: M C
authors.initials: MC
authors.lastname: Steward
mesh_terms: D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D001834:Body Water / Q000187:drug effects / Q000378:metabolism; D002118:Calcium / Q000494:pharmacology; D005110:Extracellular Space / Q000187:drug effects / Q000378:metabolism*; D005682:Gadolinium; D019786:Gadolinium DTPA; D007424:Intracellular Fluid / Q000187:drug effects / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008297:Male; D009942:Organometallic Compounds; D004369:Pentetic Acid / Q000031:analogs & derivatives; D010477:Perfusion; D051381:Rats; D017207:Rats, Sprague-Dawley; D012463:Saliva / Q000187:drug effects / Q000378:metabolism; D012469:Salivary Glands / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism*; D012636:Secretory Rate / Q000187:drug effects; D014508:Urea / Q000494:pharmacology
chemical_list: D009942:Organometallic Compounds; D004369:Pentetic Acid; D014508:Urea; D005682:Gadolinium; D019786:Gadolinium DTPA; D000109:Acetylcholine; D002118:Calcium