Release of Dopamine from Carotid Sinus Nerve Fibers Innervating Type I Cells in the Cat Carotid Body

Almaraz, L.; Wang, Z.-Z.; Stensaas, L. J.; Fidone, S.

doi:10.1159/000109474

Cited by 12 publications

(5 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The first group have nerve endings rich in TH and can synthesise catecholamines, of which dopamine is the major final form, with those fewer endings containing noradrenaline attributable to a sympathetic nerve origin (33, 277). These catecholaminergic fibers make extensive synaptic, often calyciform, contact with type I cells.…”

Section: Innervation and Communications Of The Carotid Bodymentioning

confidence: 99%

Peripheral Chemoreceptors: Function and Plasticity of the Carotid Body

Kumar

Prabhakar

2012

Comprehensive Physiology

465

572

View full text Add to dashboard Cite

The discovery of the sensory nature of the carotid body dates back to the beginning of the 20th century. Following these seminal discoveries, research into carotid body mechanisms moved forward progressively through the 20th century, with many descriptions of the ultrastructure of the organ and stimulus-response measurements at the level of the whole organ. The later part of 20th century witnessed the first descriptions of the cellular responses and electrophysiology of isolated and cultured type I and type II cells, and there now exist a number of testable hypotheses of chemotransduction. The goal of this article is to provide a comprehensive review of current concepts on sensory transduction and transmission of the hypoxic stimulus at the carotid body with an emphasis on integrating cellular mechanisms with the whole organ responses and highlighting the gaps or discrepancies in our knowledge. It is increasingly evident that in addition to hypoxia, the carotid body responds to a wide variety of blood-borne stimuli, including reduced glucose and immune-related cytokines and we therefore also consider the evidence for a polymodal function of the carotid body and its implications. It is clear that the sensory function of the carotid body exhibits considerable plasticity in response to the chronic perturbations in environmental O2 that is associated with many physiological and pathological conditions. The mechanisms and consequences of carotid body plasticity in health and disease are discussed in the final sections of this article.

show abstract

Section: Innervation and Communications Of The Carotid Bodymentioning

confidence: 99%

Peripheral Chemoreceptors: Function and Plasticity of the Carotid Body

Kumar

Prabhakar

2012

Comprehensive Physiology

465

572

View full text Add to dashboard Cite

show abstract

“…Further, the magnitude of the CSN excitatory response appears to be blunted by the concurrent action of inhibitory neurotransmitters such as GABA and dopamine (Alcayaga et al, 1999 ; Iturriaga et al, 2009 ; Nurse, 2010 ). In the case of dopamine, it is possible that its release from activated afferent C fibers during chemoexcitation may lead to autocrine-paracrine stimulation of inhibitory D2 receptors (D2R) on nearby type I cells and/or afferent nerve terminals (Benot and Lopez-Barneo, 1990 ; Almaraz et al, 1993 ; Iturriaga et al, 2003 ).…”

Section: Synaptic Transmission Between Chemoreceptor Type I Cells Andmentioning

confidence: 99%

“…These data suggest that stimulation of D2R on chemosensory petrosal neurons and their terminals causes a decrease in intracellular cAMP leading to inhibition of the cAMP-gated I h channels containing HCN4 subunits (Zhang et al, 2017 ). In this scenario, the source of dopamine is predominantly from nearby type I cells though it may include terminals of excited catecholaminergic C fibers of petrosal CB chemoafferents (Almaraz et al, 1993 ; Iturriaga et al, 2003 ).…”

Section: Synaptic Transmission Between Chemoreceptor Type I Cells Andmentioning

confidence: 99%

Sensory Processing and Integration at the Carotid Body Tripartite Synapse: Neurotransmitter Functions and Effects of Chronic Hypoxia

2018

View full text Add to dashboard Cite

Maintenance of homeostasis in the respiratory and cardiovascular systems depends on reflexes that are initiated at specialized peripheral chemoreceptors that sense changes in the chemical composition of arterial blood. In mammals, the bilaterally-paired carotid bodies (CBs) are the main peripheral chemoreceptor organs that are richly vascularized and are strategically located at the carotid bifurcation. The CBs contribute to the maintenance of O2, CO2/H+, and glucose homeostasis and have attracted much clinical interest because hyperactivity in these organs is associated with several pathophysiological conditions including sleep apnea, obstructive lung disease, heart failure, hypertension, and diabetes. In response to a decrease in O2 availability (hypoxia) and elevated CO2/H+ (acid hypercapnia), CB receptor type I (glomus) cells depolarize and release neurotransmitters that stimulate apposed chemoafferent nerve fibers. The central projections of those fibers in turn activate cardiorespiratory centers in the brainstem, leading to an increase in ventilation and sympathetic drive that helps restore blood PO2 and protect vital organs, e.g., the brain. Significant progress has been made in understanding how neurochemicals released from type I cells such as ATP, adenosine, dopamine, 5-HT, ACh, and angiotensin II help shape the CB afferent discharge during both normal and pathophysiological conditions. However, type I cells typically occur in clusters and in addition to their sensory innervation are ensheathed by the processes of neighboring glial-like, sustentacular type II cells. This morphological arrangement is reminiscent of a “tripartite synapse” and emerging evidence suggests that paracrine stimulation of type II cells by a variety of CB neurochemicals may trigger the release of “gliotransmitters” such as ATP via pannexin-1 channels. Further, recent data suggest novel mechanisms by which dopamine, acting via D2 receptors (D2R), may inhibit action potential firing at petrosal nerve endings. This review will update current ideas concerning the presynaptic and postsynaptic mechanisms that underlie chemosensory processing in the CB. Paracrine signaling pathways will be highlighted, and particularly those that allow the glial-like type II cells to participate in the integrated sensory response during exposures to chemostimuli, including acute and chronic hypoxia.

show abstract

“…As outlined above, D 2 -dopamine receptors on glomus cells likely have an autoreceptor function, but these receptors are also postsynaptic to chemoafferents that form reciprocal synapses with glomus cells (Alamaraz et al, 1993;Kummer and Habeck 1992). Retrograde tracing studies have demonstrated that a substantial number of retrogradely labeled neurons in the petrosal ganglion contain TH immunoreactivity (Alamaraz et al, 1993; or TH mRNA (Czyzyk- Krzeska et al, 1991).…”

Section: Catecholaminergic Neurotransmitter Systems Involvedmentioning

confidence: 99%

“…Retrograde tracing studies have demonstrated that a substantial number of retrogradely labeled neurons in the petrosal ganglion contain TH immunoreactivity (Alamaraz et al, 1993; or TH mRNA (Czyzyk- Krzeska et al, 1991). Furthermore, detailed experiments performed by Alamaraz et al (1993), have shown that endogenous dopamine can be measured and dopamine can be synthesized in the carotid sinus nerve of the adult cat. Thus, in adult models release of dopamine from chemoafferent neurons in response to hypoxia may also influence the chemotransduction process in the carotid body.…”

Section: Catecholaminergic Neurotransmitter Systems Involvedmentioning

confidence: 99%

Gene expression in peripheral arterial chemoreceptors

Gauda

2002

Microscopy Res & Technique

View full text Add to dashboard Cite

The peripheral arterial chemoreceptors of the carotid body participate in the ventilatory responses to hypoxia and hypercapnia, the arousal responses to asphyxial apnea, and the acclimatization to high altitude. In response to an excitatory stimuli, glomus cells in the carotid body depolarize, their intracellular calcium levels rise, and neurotransmitters are released from them. Neurotransmitters then bind to autoreceptors on glomus cells and postsynaptic receptors on chemoafferents of the carotid sinus nerve. Binding to inhibitory or excitatory receptors on chemoafferents control the electrical activity of the carotid sinus nerve, which provides the input to respiratory-related brainstem nuclei. We and others have used gene expression in the carotid body as a tool to determine what neurotransmitters mediate the response of peripheral arterial chemoreceptors to excitatory stimuli, specifically hypoxia. Data from physiological studies support the involvement of numerous putative neurotransmitters in hypoxic chemosensitivity. This article reviews how in situ hybridization histochemistry and other cellular localization techniques confirm, refute, or expand what is known about the role of dopamine, norepinephrine, substance P, acetylcholine, adenosine, and ATP in chemotransmission. In spite of some species differences, review of the available data support that 1). dopamine and norepinephrine are synthesized and released from glomus cells in all species and play an inhibitory role in hypoxic chemosensitivity; 2). substance P and acetylcholine are not synthesized in glomus cells of most species but may be made and released from nerve fibers innervating the carotid body in essentially all species; 3). adenosine and ATP are ubiquitous molecules that most likely play an excitatory role in hypoxic chemosensitivity.

show abstract

Release of Dopamine from Carotid Sinus Nerve Fibers Innervating Type I Cells in the Cat Carotid Body

Cited by 12 publications

References 35 publications

Peripheral Chemoreceptors: Function and Plasticity of the Carotid Body

Peripheral Chemoreceptors: Function and Plasticity of the Carotid Body

Sensory Processing and Integration at the Carotid Body Tripartite Synapse: Neurotransmitter Functions and Effects of Chronic Hypoxia

Gene expression in peripheral arterial chemoreceptors

Contact Info

Product

Resources

About