|
|
||||||||
The respiratory modulation of the activity of vagal cardio-inhibitory neurones of the nucleus ambiguus of the cat has been investigated by electrophysiological and neuropharmacological techniques. All twenty-four vagal efferent neurones studied had axons with conduction velocities indicative of B fibres and projected to the right cardiac branches of the vagus. Their spontaneous or DL-homocysteic acid (DLH)-evoked activity showed a marked reduction during the phase of inspiration and all showed signs of receiving a baroreceptor input. Ionophoretic application of DLH always excited cardiac vagal motoneurones (c.v.m.s). Application of acetylcholine to these same cells provoked a decrease in firing rate in twelve of the fifteen neurones tested. In ten of these twelve cells simultaneous application of atropine antagonized the effect of acetylcholine. Atropine applied alone enhanced neuronal firing, particularly in inspiration. Stable intracellular recordings have been made from two c.v.m.s. These were inhibited during inspiration. Input resistance fell markedly during inspiration and injection of chloride reversed this wave of hyperpolarization to a wave of depolarization indicating that this resulted from chloride-mediated inhibitory post-synaptic potentials (i.p.s.p.s). These c.v.m.s were activated during Stage I expiration, and showed a weak and variable wave of inhibition in Stage II expiration. Pulse-rhythmic depolarizing potentials were reduced in their amplitudes during the periods of decreased neurone input resistance. It is concluded that c.v.m.s receive an excitatory input during post-inspiration and a powerful inhibitory synaptic input during inspiration. The implications of these observations for the physiology of cardiorespiratory reflexes are discussed.
This article has been cited by other articles:
![]() |
D. M. Baekey, T. E. Dick, and J. F. R. Paton Pontomedullary transection attenuates central respiratory modulation of sympathetic discharge, heart rate and the baroreceptor reflex in the in situ rat preparation Exp Physiol, July 1, 2008; 93(7): 803 - 816. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. Kotani, K. Takamasu, Y. Jimbo, and Y. Yamamoto Postural-induced phase shift of respiratory sinus arrhythmia and blood pressure variations: insight from respiratory-phase domain analysis Am J Physiol Heart Circ Physiol, March 1, 2008; 294(3): H1481 - H1489. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. M. Hildreth, J. R. Padley, P. M. Pilowsky, and A. K. Goodchild Impaired serotonergic regulation of heart rate may underlie reduced baroreflex sensitivity in an animal model of depression Am J Physiol Heart Circ Physiol, January 1, 2008; 294(1): H474 - H480. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Kong, J.-H. Liu, A. G. Ramage, and Y. Wang Cardiovascular Control: Cardiac vagal preganglionic neurones in the intermediate zone of the brainstem in anaesthetized cats Exp Physiol, November 1, 2007; 92(6): 1023 - 1028. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y. C. Tzeng, P. D. Larsen, and D. C. Galletly Effects of hypercapnia and hypoxemia on respiratory sinus arrhythmia in conscious humans during spontaneous respiration Am J Physiol Heart Circ Physiol, May 1, 2007; 292(5): H2397 - H2407. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. J. S. Griffioen, H. W. Kamendi, C. J. Gorini, E. Bouairi, and D. Mendelowitz Reactive Oxygen Species Mediate Central Cardiorespiratory Network Responses to Acute Intermittent Hypoxia J Neurophysiol, March 1, 2007; 97(3): 2059 - 2066. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. Bouairi, H. Kamendi, X. Wang, C. Gorini, and D. Mendelowitz Multiple Types of GABAA Receptors Mediate Inhibition in Brain Stem Parasympathetic Cardiac Neurons In the Nucleus Ambiguus J Neurophysiol, December 1, 2006; 96(6): 3266 - 3272. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. A. Mandel and A. M. Schreihofer Central respiratory modulation of barosensitive neurones in rat caudal ventrolateral medulla J. Physiol., May 1, 2006; 572(3): 881 - 896. [Abstract] [Full Text] [PDF] |
||||
![]() |
V. F. Gladwell, J. Fletcher, N. Patel, L. J. Elvidge, D. Lloyd, S. Chowdhary, and J. H. Coote The influence of small fibre muscle mechanoreceptors on the cardiac vagus in humans J. Physiol., September 1, 2005; 567(2): 713 - 721. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. Jordan Vagal control of the heart: central serotonergic (5-HT) mechanisms Exp Physiol, March 1, 2005; 90(2): 175 - 181. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. Bouairi, R. Neff, C. Evans, A. Gold, M. C. Andresen, and D. Mendelowitz Respiratory sinus arrhythmia in freely moving and anesthetized rats J Appl Physiol, October 1, 2004; 97(4): 1431 - 1436. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. Yasuma and J.-i. Hayano Respiratory Sinus Arrhythmia: Why Does the Heartbeat Synchronize With Respiratory Rhythm? Chest, February 1, 2004; 125(2): 683 - 690. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. E. Cooper, T. H. Clutton-Brock, and M. J. Parkes Contribution of the respiratory rhythm to sinus arrhythmia in normal unanesthetized subjects during positive-pressure mechanical hyperventilation Am J Physiol Heart Circ Physiol, January 1, 2004; 286(1): H402 - H411. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. Mrowka, L. Cimponeriu, A. Patzak, and M. G. Rosenblum Directionality of coupling of physiological subsystems: age-related changes of cardiorespiratory interaction during different sleep stages in babies Am J Physiol Regulatory Integrative Comp Physiol, December 1, 2003; 285(6): R1395 - R1401. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. A. Neff, J. Wang, S. Baxi, C. Evans, and D. Mendelowitz Respiratory Sinus Arrhythmia: Endogenous Activation of Nicotinic Receptors Mediates Respiratory Modulation of Brainstem Cardioinhibitory Parasympathetic Neurons Circ. Res., September 19, 2003; 93(6): 565 - 572. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. E. Cooper, M. J. Parkes, and T. H. Clutton-Brock CO2-dependent components of sinus arrhythmia from the start of breath holding in humans Am J Physiol Heart Circ Physiol, July 11, 2003; 285(2): H841 - H848. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Wang, X. Wang, M. Irnaten, P. Venkatesan, C. Evans, S. Baxi, and D. Mendelowitz Endogenous Acetylcholine and Nicotine Activation Enhances GABAergic and Glycinergic Inputs to Cardiac Vagal Neurons J Neurophysiol, May 1, 2003; 89(5): 2473 - 2481. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Hayano and F. Yasuma Hypothesis: respiratory sinus arrhythmia is an intrinsic resting function of cardiopulmonary system Cardiovasc Res, April 1, 2003; 58(1): 1 - 9. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. Rentero, A. Cividjian, D. Trevaks, J. M. Pequignot, L. Quintin, and R. M. McAllen Activity patterns of cardiac vagal motoneurons in rat nucleus ambiguus Am J Physiol Regulatory Integrative Comp Physiol, December 1, 2002; 283(6): R1327 - R1334. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Ryan, W. T. McNicholas, R. G. O'Regan, and P. Nolan Effect of upper airway negative pressure and lung inflation on laryngeal motor unit activity in rabbit J Appl Physiol, January 1, 2002; 92(1): 269 - 278. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. J. Badra, W. H. Cooke, J. B. Hoag, A. A. Crossman, T. A. Kuusela, K. U. O. Tahvanainen, and D. L. Eckberg Respiratory modulation of human autonomic rhythms Am J Physiol Heart Circ Physiol, June 1, 2001; 280(6): H2674 - H2688. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Wang, M. Irnaten, and D. Mendelowitz Agatoxin-IVA-Sensitive Calcium Channels Mediate the Presynaptic and Postsynaptic Nicotinic Activation of Cardiac Vagal Neurons J Neurophysiol, January 1, 2001; 85(1): 164 - 168. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Irnaten, R. A. Neff, J. Wang, A. D. Loewy, T. C. Mettenleiter, and D. Mendelowitz Activity of Cardiorespiratory Networks Revealed by Transsynaptic Virus Expressing GFP J Neurophysiol, January 1, 2001; 85(1): 435 - 438. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. Mendelowitz Advances in Parasympathetic Control of Heart Rate and Cardiac Function Physiology, August 1, 1999; 14(4): 155 - 161. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. W. Taylor, D. Jordan, and J. H. Coote Central Control of the Cardiovascular and Respiratory Systems and Their Interactions in Vertebrates Physiol Rev, July 1, 1999; 79(3): 855 - 916. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. A. Neff, J. Humphrey, M. Mihalevich, and D. Mendelowitz Nicotine Enhances Presynaptic and Postsynaptic Glutamatergic Neurotransmission to Activate Cardiac Parasympathetic Neurons Circ. Res., December 14, 1998; 83(12): 1241 - 1247. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. Montano, C. Cogliati, A. Porta, M. Pagani, A. Malliani, K. Narkiewicz, F. M. Abboud, C. Birkett, and V. K. Somers Central Vagotonic Effects of Atropine Modulate Spectral Oscillations of Sympathetic Nerve Activity Circulation, October 6, 1998; 98(14): 1394 - 1399. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. Sasano, A. E. Vesely, J. Hayano, H. Sasano, R. Somogyi, D. Preiss, K. Miyasaka, H. Katsuya, S. Iscoe, and J. A. Fisher Direct effect of PaCO2 on respiratory sinus arrhythmia in conscious humans Am J Physiol Heart Circ Physiol, March 1, 2002; 282(3): H973 - H976. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |