Opioid‐receptor‐mediated excitation of rat mesenteric afferent fibres supplying the rat jejunum

Eastwood, C.; Grundy, David

doi:10.1046/j.1365-2982.2000.00226.x

Cited by 14 publications

(14 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In addition, certain mu opiates such as the enkephalin derivative DAMGO stimulate mesenteric afferents action potentials which are blocked by the opioid receptor antagonist alvimopan [121]. Mesenteric afferents respond with increasing firing rate when exposed to mu and delta receptor agonists which does not occur with selective kappa receptor agonists [122, 123]. Morphine has been shown to increase the visceral hypersensitivity and viscerosomatic referral in animal models of colitis and irritable bowel syndrome (caused by butyrate) [124].…”

Section: Important Channels Receptors and Mediators Of Visceral mentioning

confidence: 99%

Drug Management of Visceral Pain: Concepts from Basic Research

Davis

2012

Pain Research and Treatment

View full text Add to dashboard Cite

Visceral pain is experienced by 40% of the population, and 28% of cancer patients suffer from pain arising from intra- abdominal metastasis or from treatment. Neuroanatomy of visceral nociception and neurotransmitters, receptors, and ion channels that modulate visceral pain are qualitatively or quantitatively different from those that modulate somatic and neuropathic pain. Visceral pain should be recognized as distinct pain phenotype. TRPV1, Na 1.8, and ASIC3 ion channels and peripheral kappa opioid receptors are important mediators of visceral pain. Mu agonists, gabapentinoids, and GABAB agonists reduce pain by binding to central receptors and channels. Combinations of analgesics and adjuvants in animal models have supra-additive antinociception and should be considered in clinical trials. This paper will discuss the neuroanatomy, receptors, ion channels, and neurotransmitters important to visceral pain and provide a basic science rationale for analgesic trials and management.

show abstract

Section: Important Channels Receptors and Mediators Of Visceral mentioning

confidence: 99%

Drug Management of Visceral Pain: Concepts from Basic Research

Davis

2012

Pain Research and Treatment

View full text Add to dashboard Cite

show abstract

“…20 Consistent with this view is the observation that opioid receptors are expressed on vagal sensory neurones, and agonists acting at µ and δ receptors can activate vagal afferent pathways. 21 This activation occurs at doses of opioids that are well below analgesic levels. Moreover, fibres that respond to opioids also respond to other endogenous signals generated from within the gastro-intestinal tract, in particular those activated by low levels of mechanical stimulation and nutrients.…”

Section: Mechanosensitivitymentioning

confidence: 99%

Neuroanatomy of visceral nociception: vagal and splanchnic afferent

Grundy

2002

Gut

220

161

View full text Add to dashboard Cite

“…Furthermore, variable somatic and vagal sensory neural responses to the activation of opioid receptors have been reported (2,9,10,25,30,52). In this regard, the -receptor agonist [D-Ala 2 , N-MePhe 4 , Glyol]-enkephalin (DAMGO) directly excites rat small intestinal afferent nerves (11). Similarly, activation of peripheral opioid -, ␦-, and -receptors increases the discharge activity of testis-spermatic sensory nerves of dogs (30).…”

Section: Discussionmentioning

confidence: 99%

Functional role of peripheral opioid receptors in the regulation of cardiac spinal afferent nerve activity during myocardial ischemia

Longhurst

2013

American Journal of Physiology-Heart and Circulatory Physiology

View full text Add to dashboard Cite

Fu LW, Longhurst JC. Functional role of peripheral opioid receptors in the regulation of cardiac spinal afferent nerve activity during myocardial ischemia. Am J Physiol Heart Circ Physiol 305: H76-H85, 2013. First published May 3, 2013 doi:10.1152/ajpheart.00091.2013.-Thinly myelinated A␦-fiber and unmyelinated C-fiber cardiac sympathetic (spinal) sensory nerve fibers are activated during myocardial ischemia to transmit the sensation of angina pectoris. Although recent observations showed that myocardial ischemia increases the concentrations of opioid peptides and that the stimulation of peripheral opioid receptors inhibits chemically induced visceral and somatic nociception, the role of opioids in cardiac spinal afferent signaling during myocardial ischemia has not been studied. The present study tested the hypothesis that peripheral opioid receptors modulate cardiac spinal afferent nerve activity during myocardial ischemia by suppressing the responses of cardiac afferent nerve to ischemic mediators like bradykinin and extracellular ATP. The nerve activity of single unit cardiac afferents was recorded from the left sympathetic chain (T2-T5) in anesthetized cats. Forty-three ischemically sensitive afferent nerves (conduction velocity: 0.32-3.90 m/s) with receptive fields in the left and right ventricles were identified. The responses of these afferent nerves to repeat ischemia or ischemic mediators were further studied in the following protocols. First, epicardial administration of naloxone (8 mol), a nonselective opioid receptor antagonist, enhanced the responses of eight cardiac afferent nerves to recurrent myocardial ischemia by 62%, whereas epicardial application of vehicle (PBS) did not alter the responses of seven other cardiac afferent nerves to ischemia. Second, naloxone applied to the epicardial surface facilitated the responses of seven cardiac afferent nerves to epicardial ATP by 76%. Third, administration of naloxone enhanced the responses of seven other afferent nerves to bradykinin by 85%. In contrast, in the absence of naloxone, cardiac afferent nerves consistently responded to repeated application of ATP (n ϭ 7) or bradykinin (n ϭ 7). These data suggest that peripheral opioid peptides suppress the responses of cardiac sympathetic afferent nerves to myocardial ischemia and ischemic mediators like ATP and bradykinin. sympathetic afferent nerves; opioid receptors; myocardial ischemia; naloxone ACTIVATION of thinly myelinated A␦-fiber and unmyelinated C-fiber cardiac sympathetic (spinal) afferent nerves during myocardial ischemia is responsible for the transmission of information from the heart to the brain that ultimately elicits the perception of cardiac pain and evokes excitatory cardiaccardiovascular reflex responses (19,22,39). For many years, attention has been focused on characterizing the excitatory effects elicited by a number of ischemic mediators on cardiac spinal afferent nerve activity during myocardial ischemia. In contrast, inhibitory influences of ischemic mediators on cardiac spinal...

show abstract

Opioid‐receptor‐mediated excitation of rat mesenteric afferent fibres supplying the rat jejunum

Cited by 14 publications

References 24 publications

Drug Management of Visceral Pain: Concepts from Basic Research

Drug Management of Visceral Pain: Concepts from Basic Research

Neuroanatomy of visceral nociception: vagal and splanchnic afferent

Functional role of peripheral opioid receptors in the regulation of cardiac spinal afferent nerve activity during myocardial ischemia

Contact Info

Product

Resources

About