title: A system for applying rapid warming or cooling stimuli to cells during patch clamp recording or ion imaging.
abstract: We describe a system for superfusing small groups of cells at a precisely controlled and rapidly adjustable local temperature. Before being applied to the cell or cells under study, solutions are heated or cooled in a chamber of small volume ( approximately 150 microl) and large surface area, sandwiched between four small Peltier elements. The current through the Peltier elements is controlled by a microprocessor using a PID (proportional-integral-derivative) feedback algorithm. The chamber can be heated to at least 60 degrees C and cooled to 0 degrees C, changing its temperature at a maximum rate of about 7 degrees C per second; temperature ramps can be followed under feedback control at up to 4 degrees C per second. Temperature commands can be applied from the digital-to-analogue converter of any laboratory interface or generated digitally by the microprocessor. The peak-to-peak noise contributed by the system does not exceed that contributed by a patch pipette, holder and headstage, making it suitable for single channel as well as whole cell recordings.
authors.affiliation: Department of Animal Physiology and Biophysics, Faculty of Biology, University of Bucharest, Splaiul Independentei 91-95, 76201, Bucharest, Romania. gordon@biologie.kappa.ro
authors.forename: G
authors.initials: G
authors.lastname: Reid
authors.forename: B
authors.initials: B
authors.lastname: Amuzescu
authors.forename: E
authors.initials: E
authors.lastname: Zech
authors.forename: M L
authors.initials: ML
authors.lastname: Flonta
mesh_terms: D000200:Action Potentials / Q000502:physiology; D000818:Animals; D001831:Body Temperature / Q000502:physiology*; D018929:Cell Culture Techniques / Q000295:instrumentation / Q000379:methods; D002478:Cells, Cultured; D015194:Diffusion Chambers, Culture / Q000295:instrumentation / Q000379:methods; D004582:Electronics, Medical / Q000295:instrumentation / Q000379:methods; D004780:Environment, Controlled; D005246:Feedback / Q000502:physiology; D005727:Ganglia, Spinal / Q000166:cytology / Q000502:physiology; D006361:Heating / Q000295:instrumentation* / Q000379:methods; D007036:Hypothermia, Induced / Q000295:instrumentation* / Q000379:methods; D007477:Ions / Q000032:analysis; D009475:Neurons, Afferent / Q000502:physiology; D018408:Patch-Clamp Techniques / Q000295:instrumentation / Q000379:methods*; D010477:Perfusion / Q000295:instrumentation* / Q000379:methods; D051381:Rats; D015398:Signal Transduction / Q000502:physiology; D013697:Thermosensing / Q000502:physiology
chemical_list: D007477:Ions