Suction electrode in frog heart ventricle (part 2)

Histological data of myocardial cells exposed to contact pressure to elucidate injury are still lacking. MAP recording can be produced by nontraumatic interventions (contact catheter) and by a pressure of 10 g/mm , which is comparable with three times the normal intraventricular blood pressure. Further indirect evidence for a lack of significant tissue injury may be derived from the stable amplitude of MAP over hours of recording from the same endocardial or epicar-dial site.Contraction-excitation coupling, or mechano-electrical feedback, can lead to changes in action potential duration and diastolic potential, and afterdepolarizations and arrhythmias. One mechanism that may produce these electrophysiological effects is myocardial stretch. We used suction-evoked MAP in the heart to elucidate ionic, biochemical and structural processes under a suction electrode, which play a role in short lasting mechanical dilation.

Animals: Frogs (Rana temporaria) were pithed (brain and spinal cord), and the thorax was opened (n=200). The investigation conformed with the Guide for the Care and Use of Laboratory Animals. Online shopping will cost you less – find cheap mircette and enjoy the experience.


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