title: A stimulus timing device for capturing fast physiologic events by quick-freezing.
abstract: A timing device was designed that, in conjunction with an impact type of quick-freezing apparatus and an externally-triggerable stimulus generator, allows the application of an electrical stimulus to a muscle preparation at a selected time interval before quick-freezing and the measurement of the interval with submillisecond precision. This is needed for stopping fast physiological events in calcium release and excitation-contraction coupling and allows studying the morphological parameters (by freeze-fracture and freeze-substitution) and elemental distributions (by x-ray microanalysis) as a function of time after stimulation. The device should be adaptable for use with most equipment designed for quick-freezing electrically excitable tissue by impact on a cold solid surface.
authors.affiliation: Department of Cell Biology, Duke University Medical Center, Durham, NC 27710.
authors.forename: R
authors.initials: R
authors.lastname: Nassar
authors.forename: J R
authors.initials: JR
authors.lastname: Sommer
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism; D004558:Electric Stimulation / Q000295:instrumentation; D005614:Freeze Fracturing / Q000295:instrumentation* / Q000379:methods; D017110:Freeze Substitution / Q000295:instrumentation* / Q000379:methods; D009119:Muscle Contraction / Q000502:physiology*; D009132:Muscles / Q000033:anatomy & histology / Q000502:physiology*; D011898:Ranidae; D013997:Time Factors
chemical_list: D002118:Calcium