Circus-movement tachycardia in frog atrium monitored by voltage-sensitive dyes.

Abstract

Circus-movement tachycardia was studied using voltage-sensitive merocyanine-rhodanine dyes (dye XVII and NK2761). Excitatory waves were optically measured simultaneously from eight different regions of a ring of tissue formed from frog atrium. Application of acetylcholine in Ca2+-free solution (10(-10)-10(-9) g/ml) shortened the duration of optical action signals to cause nonuniform change in optical signal durations in about 60% of the preparations. Circus-movement tachycardia was produced by proper reduction and regional nonuniformity of optical signal durations. Under these circumstances it is easy to evoke circus-movement tachycardia by giving an extra stimulus to the site that shows a difference in optical signal durations.

• Authors: T Sawanobori, Y Hirano, A Hirota, S Fujii
• Journal: The American journal of physiology (Am J Physiol) Vol. 247 Issue 2 Pt 2 Pg. H185-94 (Aug 1984) ISSN: 0002-9513 [Print] United States
• PMID: 6331771 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Benzoxazoles
• Fluorescent Dyes
• Thiazoles
• Thiazolidines
• merocyanine-rhodanine
• Rhodanine
• Acetylcholine

Topics

• Acetylcholine (pharmacology)
• Action Potentials (drug effects)
• Animals
• Benzoxazoles (metabolism)
• Fluorescent Dyes (metabolism)
• Heart (physiopathology)
• Heart Atria (physiopathology)
• Microelectrodes
• Rana catesbeiana
• Rhodanine (analogs & derivatives, metabolism)
• Tachycardia (physiopathology)
• Thiazoles (metabolism)
• Thiazolidines