Accumulation of cAMP augments dynamic vagal control of heart rate

The American Journal of Physiology
T NakaharaK Sunagawa

Abstract

Recent investigations in our laboratory using a Gaussian white noise perturbation technique have shown that simultaneous sympathetic stimulation augmented the gain of the transfer function from vagal stimulation frequency to heart rate response. However, the mechanism of that augmentation remains to be elucidated. In this study, we examined in anesthetized rabbits how three pharmacological interventions known to cause intracellular accumulation of cAMP affected the transfer function. Isoproterenol (0.3 microg . kg-1 . min-1 iv) increased the dynamic gain of transfer function from 7.12 +/- 0.67 to 12.4 +/- 1.21 beats . min-1 . Hz-1 (P < 0.05) without changing the corner frequency or the lag time. Similar augmentations were observed when forskolin (5 microg . kg-1 . min-1 iv) or theophylline (20 mg/kg iv) was administered under conditions of beta-adrenergic blockade. These results suggest that the accumulation of cAMP at postjunctional effector sites contributes, at least in part, to the sympathetic augmentation of the dynamic vagal control of heart rate.

References

Oct 1, 1990·The Journal of General Physiology·T NakajimaW Giles
Jan 1, 1990·Annals of the New York Academy of Sciences·M N Levy
Oct 1, 1985·Pflügers Archiv : European journal of physiology·M KameyamaW Trautwein
Aug 1, 1986·Pflügers Archiv : European journal of physiology·J HeschelerW Trautwein
Nov 1, 1971·Circulation Research·M N Levy
Jul 1, 1995·The Journal of General Physiology·X HanW R Giles
Apr 15, 1994·The Journal of Physiology·X HanW R Giles
Nov 1, 1993·Cardiovascular Research·S BartelE G Krause
Jan 1, 1993·Physiological Reviews·H IrisawaW Giles
Apr 1, 1993·Pflügers Archiv : European journal of physiology·J Petit-JacquesJ Lenfant
Sep 1, 1996·Circulation Research·R A KellyT W Smith

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Citations

Mar 15, 2001·American Journal of Physiology. Heart and Circulatory Physiology·T KawadaK Sunagawa
Feb 25, 2003·American Journal of Physiology. Heart and Circulatory Physiology·Tadayoshi MiyamotoKenji Sunagawa
Mar 16, 2004·American Journal of Physiology. Heart and Circulatory Physiology·Tadayoshi MiyamotoKenji Sunagawa
Mar 3, 2009·American Journal of Physiology. Heart and Circulatory Physiology·Toru KawadaMasaru Sugimachi
May 29, 2007·American Journal of Physiology. Heart and Circulatory Physiology·Masaki MizunoMasaru Sugimachi
Apr 24, 2021·American Journal of Physiology. Heart and Circulatory Physiology·Toru KawadaMasaru Sugimachi

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