Search results for "Opioidergic"
showing 6 items of 6 documents
Central opioidergic neurotransmission in complex regional pain syndrome
2010
Objective: Complex regional pain syndrome (CRPS) is a chronic pain condition characterized by sensory, motor, and autonomic symptoms. It develops after limb trauma and may be associated with relevant psychiatric comorbidity. As there is evidence for central pathophysiology which might be related to an altered opioidergic neurotransmission, we investigated the cerebral opioid receptor status under resting conditions in this patient population.Methods: In this case-control study, 10 patients with CRPS and 10 age- and gender-matched healthy subjects underwent a PET scan using the subtype-nonselective opioidergic radioligand [18F]fluoroethyl-diprenorphine. As a surrogate for regional cerebral o…
Evidence for modulation of opioidergic activity in central vestibular processing: A [(18)F] diprenorphine PET study.
2009
Animal and functional imaging studies had identified cortical structures such as the parieto‐insular vestibular cortex, the retro‐insular cortex, or the anterior cingulate cortex belonging to a vestibular cortical network. Basic animal studies revealed that endorphins might be important transmitters involved in cerebral vestibular processing. The aim of the present study was therefore to analyse whether the opioid system is involved in vestibular neurotransmission of humans or not. Changes in opioid receptor availability during caloric air stimulation of the right ear were studied with [(18)F] Fluoroethyl‐diprenorphine ([(18)F]FEDPN) PET scans in 10 right‐handed healthy volunteers and compa…
Opioid receptor PET reveals the psychobiologic correlates of reward processing.
2008
Little is known about the neurobiologic correlates of human personality. On the basis of the key role of the central opioidergic system in addiction and substance abuse, we investigated the relationship between certain personality traits that are supposed to be relevant in addiction and the opioid receptor status in healthy subjects.We investigated 23 healthy male volunteers who were extensively clinically tested to exclude substance abuse. All of the subjects underwent 1 PET scan with the subtype-nonselective opioidergic radioligand 18F-fluoroethyl-diprenorphine under resting conditions without sensory or cognitive stimulation. Subsequently, the subjects were psychologically tested for the…
Naloxone inhibits not only stress-induced analgesia but also sympathetic activation and baroreceptor-reflex sensitivity
2012
Interactions between the sympathetic nervous system and pain are manifold and still have not been sufficiently characterized. Accordingly, several possible neuronal pathways have been described as being involved in mental stress-induced analgesia. We studied the role of the endogenous opioidergic system in stress-induced analgesia in 14 healthy participants in a double-blind cross-over trial. Naloxone or placebo was applied while electrical pain stimulation was started and electrical current increased. After reaching a constant stimulation at 30 mA, a color word interference test (Stroop task) was performed in a stressful and a non-stressful version. Blood pressure, heart rate and barorefle…
Multiplicity of Opioidergic Pathways Related to Cardiovascular Innervation: Differential Contribution of All Three Opioid Precursors
1988
The endogenous opioid family consists of the three precursors proenkephalin (proenkephalin A), prodynorphin (proenkephalin B), and proopiomelanocortin (POMC), from which various opioid and nonopioid peptides can be processed, apparently in a tissue-specific manner (cf. Civelli et al. 1984; Goldstein 1984; Herz 1984; Udenfriend and Kilpatrick 1984; Civelli et al. 1985; Khachaturian et al. 1985; Kosterlitz 1985). Their distribution in areas of the CNS which are involved in cardiovascular regulation is well documented. The biochemistry and functions of endocrine (pituitary and adrenal) opioids have also been well characterized (cf. Millan and Herz 1985). The conception that endocrine and CNS o…
Pro-enkephalin opioid peptides are abundant in porcine and bovine splenic nerves, but absent from nerves of rat, mouse, hamster, and guinea-pig spleen
1995
The opioidergic innervation of the mammalian spleen and possible species differences were investigated. Light-microscopic immunohistochemistry revealed that splenic nerves of bovine and porcine spleen, but not of rat, mouse, hamster and guinea-pig spleen contained proenkephalin-derived opioidergic innervation. Immunoreactivity to both prodynorphin and pro-opiomelanocortin was absent from splenic nerves. In bovine and porcine spleen, fibers immunoreactive for met-enkephalin, met-enkephalin-Arg-Phe, met-enkephalin-Arg-Gly-Leu, leu-enkephalin and peptide F formed perivascular plexus, traveled in trabecular connective tissue, and extended into the capsule. Spatial relationships with immune cell…