Pacemaker Shift in the Rabbit Sinoatrial Node in Response to Vagal Nerve Stimulation
نویسندگان
چکیده
منابع مشابه
Vagal control of pacemaker periodicity and intranodal conduction in the rabbit sinoatrial node.
Effects of brief vagal bursting on pacemaker periodicity and intranodal conduction were studied by recording transmembrane potentials in isolated rabbit sinoatrial preparations. Postganglionic vagal terminals were activated by applying brief (50- to 150-msec) trains of pulses (duration, 100 mu sec; frequency, 200 Hz) to the endocardial surface of the node. Sympathetic effects were prevented by ...
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The effects of intercellular coupling conductance on the activity of two electrically coupled isolated rabbit sinoatrial nodal cells were investigated. A computer-controlled version of the "coupling clamp" technique was used in which isolated sinoatrial nodal cells, not physically in contact with each other, were electrically coupled at various values of ohmic coupling conductance, mimicking th...
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Vagal stimulation results in complex changes of pacemaker excitability in the sinoatrial node (SAN). To investigate the vagal effects in the rabbit SAN, we used optical mapping, which is the only technology that allows resolving simultaneous changes in the activation pattern and action potentials morphologies. With the use of immunolabeling, we identified the SAN as a neurofilament 160-positive...
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Dynamic heart rate control by parasympathetic nervous input involves feedback mechanisms and reflex bursting of efferent cardiac vagal fibers. Periodic vagal bursting induces phasic changes in sinoatrial cycle length and can entrain the pacemaker to beat at periods that may be identical to those of the vagal burst. We investigated the electrophysiological basis of these phenomena in isolated si...
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ژورنال
عنوان ژورنال: Experimental Physiology
سال: 2001
ISSN: 0958-0670
DOI: 10.1113/eph8602100