Cardiovascular reflexes and interrelationships between sympathetic and parasympathetic activity

Mark Kollai, Kiyomi Koizumi

Research output: Contribution to journalArticle

42 Citations (Scopus)


Simultaneous recordings from vagal and sympathetic nerve fibers innervating the heart have enabled us to study relationships between activity in these two autonomic nerves. Our recent studies, as well as those of others, are reviewed with respect to tonic activity and reflex actions in these two autonomic efferents. Discharges of the two nerves in relation to blood pressure pulses and to respiratory cycles are reciprocal. During slower fluctuations of hemodynamic changes which occur spontaneously, such as during Mayer waves, a reciprocal relationship between activity in the two autonomic nerves is also observed. On the other hand, in reflex responses both reciprocal and non-reciprocal patterns of reactions occur, depending on the sensory receptors stimulated. Also, reactions produced by stimulations of the hypothalamus showed varied relationships between responses in the two autonomic outflows. The functional significance of the interrelationships of the activity pattern observed in vagal and sympathetic nerves is discussed with respect to control of cardiac functions.

Original languageEnglish
Pages (from-to)135-148
Number of pages14
JournalJournal of the Autonomic Nervous System
Issue number2
Publication statusPublished - Jul 1981



  • autonomic nervous system
  • autonomic reflex
  • cardiac sympathetic nerve
  • cardiac vagus nerve
  • neural control of the heart
  • non-reciprocal control
  • reciprocal control
  • tonic activity

ASJC Scopus subject areas

  • Neuroscience(all)
  • Physiology
  • Clinical Neurology

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