Am. J. Respir. Crit. Care Med., Volume 164, Number 10, November 2001, 1927-1932

The Integrative Membrane Properties of Human Bronchial Parasympathetic Ganglia Neurons

RADHIKA KAJEKAR, HOLLY K. ROHDE, and ALLEN C. MYERS

Department of Medicine, Division of Clinical Immunology, The Johns Hopkins University School of Medicine, Baltimore, Maryland

Parasympathetic ganglia neurons in the lower airway of laboratory animals have membrane properties associated with integration of signals from the central nervous system. In this study, intracellular recordings were made from parasympathetic ganglia located on bronchi from human lungs in order to determine the level of integration provided by human neurons. Ganglion neurons were characterized as either tonic or phasic: tonic neurons responded with repetitive action potentials sustained throughout a depolarizing current step whereas phasic neurons generated one action potential and accommodated. Phasic neurons could be further differentiated as having either short or long duration afterhyperpolarizing potentials following single action potentials. In phasic neurons, stimulation of preganglionic nerves elicited one or two populations of nicotinic fast excitatory postsynaptic potentials (fEPSPs) that were graded in amplitude, subthreshold for action potential generation, and decreased in amplitude during higher frequency stimulation. In tonic neurons, single preganglionic stimuli evoked two to five populations of fEPSPs, one to three of which were at threshold for action potential generation. Dye injection into the neurons revealed multiple, branching dendrites. These results provide evidence that human bronchial ganglion neurons have unique membrane properties and anatomical characteristics associated with integrating presynaptic stimuli. Changes in these properties may thus affect output from these ganglia and, consequently, autonomic tone in the lower airways.

This article has been cited by other articles:

				A. G. Duarte, L. Terminella, J. T. Smith, A. C. Myers, G. Campbell, and S. Lick Restoration of Cough Reflex in Lung Transplant Recipients Chest, August 1, 2008; 134(2): 310 - 316. [Abstract] [Full Text] [PDF]

				M. S. Hazari, J. H. Pan, and A. C. Myers Nerve growth factor acutely potentiates synaptic transmission in vitro and induces dendritic growth in vivo on adult neurons in airway parasympathetic ganglia Am J Physiol Lung Cell Mol Physiol, April 1, 2007; 292(4): L992 - L1001. [Abstract] [Full Text] [PDF]

				A. C. Myers, R. G. Goldie, and D. W. P. Hay A Novel Role for Tachykinin Neurokinin-3 Receptors in Regulation of Human Bronchial Ganglia Neurons Am. J. Respir. Crit. Care Med., February 1, 2005; 171(3): 212 - 216. [Abstract] [Full Text] [PDF]

				B. J. Canning, S. M. Reynolds, L. U. Anukwu, R. Kajekar, and A. C. Myers Endogenous neurokinins facilitate synaptic transmission in guinea pig airway parasympathetic ganglia Am J Physiol Regulatory Integrative Comp Physiol, August 1, 2002; 283(2): R320 - R330. [Abstract] [Full Text] [PDF]

				M. J. TOBIN Asthma, Airway Biology, and Nasal Disorders in AJRCCM 2001 Am. J. Respir. Crit. Care Med., March 1, 2002; 165(5): 598 - 618. [Full Text] [PDF]