Relationship of Ca2+ sparks to STOCs studied with 2D and 3D imaging in feline oesophageal smooth muscle cells

UMMS Affiliation

Department of Physiology and Biomedical Imaging Group

Publication Date


Document Type



Aniline Compounds; Animals; Calcium; Cats; Cell Membrane; Electric Conductivity; Esophagus; Fluorescent Dyes; Image Processing, Computer-Assisted; Imaging, Three-Dimensional; Muscle, Smooth; Patch-Clamp Techniques; Xanthenes


Life Sciences | Medicine and Health Sciences


We recorded Ca2+ sparks and spontaneous transient outward currents (STOCs) simultaneously in smooth muscle cells using whole-cell patch recording and a unique, high-speed widefield digital imaging system to monitor fluo-3 fluorescence in both two and three dimensions (2D and 3D). In 2D imaging, the correlation between the amplitude of a spark and its corresponding STOC was a weak one, and 27 % of the sparks failed to cause STOCs. The STOCless sparks were not significantly different in amplitude from those that caused STOCs. Three-dimensional imaging disclosed that STOCless sparks were located close to the cell surface, and on average their apparent distance from the cell surface was not significantly different from the sparks that cause STOCs. Statistical evaluation of spark clusters disclosed that there were regions of the cell where the probability of spark occurrence was high and others where it was quite low.


J Physiol. 2001 Mar 1;531(Pt 2):315-27.

Journal/Book/Conference Title

The Journal of physiology

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Link to Article in PubMed

PubMed ID