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PubMed · 1439666

A stimulus timing device for capturing fast physiologic events by quick-freezing.

R Nassar·J R Sommer
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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.

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AnimalsCalciumElectric StimulationFreeze FracturingFreeze SubstitutionMuscle ContractionMusclesRanidaeTime FactorsJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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R Nassar, J R Sommer. 1992. A stimulus timing device for capturing fast physiologic events by quick-freezing.. https://pubmed.ncbi.nlm.nih.gov/1439666/

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