Paradoxical Dynamic Interaction of Heart Period and Vagal Activity on Atrioventricular Conduction in the Dog
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چکیده
duced by brainstem lesions in the rat. Circ Res 32: 584-593, 1973 10. Badr GG, Lindholm LE: A simple method for connecting chronically implanted electrodes. Physiol Behav 9: 487-488, 1972 11. Snedecor GW: Statistical Methods Applied to Experiments in Agriculture and Biology. Ames, Iowa State University Press, 1967 12. Guazzi M, Zanchetti A: Blood pressure and heart rate during natural sleep of the cat and their regulation by carotid sinus and aortic reflexes. Arch Ital Biol 103: 789-817, 1965 13. Ito CS, Scher AM: Arterial baroreceptor fibers from the aortic region of the dog in the cervical vagus nerve. Circ Res 32: 442-446, 1973 14. Ito CS, Scher AM: Reflexes from the aortic baroreceptor fibers in the cervical vagus of the cat and the dog. Circ Res 34: 51-60, 1974
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Paradoxical dynamic interaction of heart period and vagal activity on atrioventricular conduction in the dog.
The dynamic interaction of simultaneously changing heart period and single vagal stimuli on atrioventricular conduction (AV interval) was quantified by subtracting the vagally induced responses of the paced heart preparation from those of the unpaced heart preparation. This difference was significantly greater (P less than 0.05) than the AV responses to changes in heart period (delta A) alone w...
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The vagal system regulates the atrioventricular conduction time ( T AV) via two opposing mechanisms: a direct effect on the atrioventricular node and an indirect effect through changes in heart period ( T AA). To evaluate how dynamic vagal activation affects T AV, we stimulated the vagal nerve with frequency-modulated Gaussian white noise and estimated the transfer function from vagal stimulati...
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