Medical College of Wisconsin
CTSICores SearchResearch InformaticsREDCap

Recurrent laryngeal nerve activation by alpha 2 adrenergic agonists in goats. Respir Physiol 1995 Aug;101(2):129-37 PMID: 8570915

Pubmed ID



The purpose of this study was to test the hypothesis that respiratory and apneas induced by alpha 2 agonists in anesthetized goats are associated with an increase of upper airway expiratory-related activity, rather than a general depression of breathing. Activities of phrenic (Phr) and recurrent laryngeal nerves (RLN) were recorded in response to the alpha 2 agonists clonidine (0.5-3.0 i.v.) or guanabenz (7.0-20.0 i.v.) in ten chloralose-anesthetized goats. Injection of either alpha 2 agonist resulted in respiratory arrhythmias with a greater than seven-fold increase in TE and a 30% reduction in TI. During apneas RLN expiratory-related activity remained tonic until the next Phr burst, consistent with our hypothesis. Cessation of Phr activity during hypocapnia also resulted in a tonic increase of RLN expiratory activity; and injection of NaCN (50 i.v.) increased Phr and RLN inspiratory activities, while attenuating RLN expiratory-related activity. Inspiratory and expiratory-related activity of RLN motoneurons appear to be reciprocally modulated by alpha 2 agonists or changes in central or peripheral chemoreceptor drive. The results indicate that central apneas and respiratory arrhythmias may be associated with alpha 2-adrenoceptor modulation of laryngeal expiratory-related activity.

Author List

Hedrick MS, Ryan ML, Bisgard GE


Melinda R. Dwinell PhD Center Associate Director, Associate Professor in the Physiology department at Medical College of Wisconsin


2-s2.0-0029143789   15 Citations

MESH terms used to index this publication - Major topics in bold

Adrenergic alpha-Agonists
Adrenergic alpha-Antagonists
Carbon Dioxide
Chemoreceptor Cells
Partial Pressure
Phrenic Nerve
Recurrent Laryngeal Nerve
Sodium Cyanide
jenkins-FCD Prod-331 a335b1a6d1e9c32173c9534e6f6ff51494143916