Cardiac sensory afferents: The cornerstone for autonomic reflex processing in health and disease

Symposium — Sunday, April 23, 2024 — 8:00 AM - 10:00 AM — , Room W196C
Neural Control and Autonomic Regulation Section — Chair: Kalyanam Shivkumar — Co-Chair: Hanjun Wang

Coordination cardiac electrical and mechanical function depends on interactions that occur among the collections of neurons located at multiple levels of the central and peripheral nervous systems. Recent data indicate that the cardiac neuronal hierarchy is made up of interdependent feedback loops comprising somata located in i) intrinsic cardiac ganglia, ii) intrathoracic extracardiac (stellate, middle cervical) and iii) superior cervical ganglia as well as iv) the spinal cord, v) brainstem and vi) higher centers (up to the insular cortex). Each of these processing center contains afferent, efferent and integrative (local circuit ones in peripheral ganglia) neurons which interact locally and in an interdependent fashion with other levels to coordinate regional cardiac indices on a beat-to-beat basis.  While this network is optimized to respond to normal environmental stressors (standing, exercise); it can be catastrophically disrupted by pathologies such as myocardial ischemia (MI). In fact, it is now recognized that autonomic dysregulation is central to the evolution of heart failure and arrhythmias.  

The central theme of the proposed symposia is Cardiac sensory afferents: The cornerstone for autonomic reflex processing in health and disease.  Emerging concepts in integration of central and peripheral reflexes will be considered in normal and pathological conditions.  Dr. Jeff Ardell (UCLA) will first discuss the structure/function organization of intrathoracic reflexes providing insights derived from recent advances in cardioneural mapping.  Dr. Stephen Liberles (Harvard) has developed state-of-the-art tools for studying the vagus nerve, nodose ganglia and vago-vagus reflexes. His laboratory has developed new mouse models, and co-opted powerful tools for anatomical tracing, in vivo imaging, single cell transcriptomics, and remote control of neural activity to study interoception.  His talk will focus on structure/function organization of nodose afferents and vago-vagal reflexes.  Dr. Robert Foreman (Oklahoma Health Science Center) will then discuss translational aspects of spinal cord neural processing as related to autonomic control and its utility as a target for bioelectric medicine.  Finally, Dr. Michael Andresen (Oregon Health and Science University) will focus on information processing of primary visceral afferents including baroreceptors within the solitary tract nucleus (NTS) and the potential for differential control of central efferent drive.

Speakers

• Structure/function organization of intrathoracic reflexes
  Jeffrey Ardell — UCLA Arrhythmia Center, UCLA


• Structure/function organization of nodose afferents and vago-vagal reflexes
  Stephen Liberles — Cell Biology, Harvard Medical School


• Spinal cord processing of visceral afferent activity
  Robert Foreman — Physiology, Oklahoma Health Sciences Center


• Medullary processing of cranial visceral afferent signals
  Michael Andresen — Dept of Physiology and Pharmacology, Oregon Health and Science University