Abstract
Multiple-site optical recording methods, using a fast voltage-sensitive merocyanine-rhodanine dye (NK2761) and a multi-element (16 X 16) photodiode array, were employed to simultaneously monitor action potentials from many sites in the isolated rat atrium preparation. Cytochalasin D was used to reduce contraction-related optical artefacts by suppressing muscle contraction without affecting electrical action potential. The suppression effect of this chemical (40μM) on the contraction-related optical artefacts is time-dependent for the first 30 min. and become steady state within 40–60 min. after the application to the bath. The suppression of the artefact of this chemical is generally stronger than that of 2,3-butanedione monoxime (BDM: 20 mM). Using this chemical, we successively evoked tachycardia-like excitation (TE) in the isolated rat right atrium preparation and mapped optically the excitation spread pattern during TE. [J Physiol Sci. 2006;56 Suppl:S126]
