In Pain Perception (in + pain_perception)

Distribution by Scientific Domains


Selected Abstracts


Role of botulinum toxin in migraine therapy

DRUG DEVELOPMENT RESEARCH, Issue 7 2007
Wilhelm J. Schulte-Mattler
Abstract Botulinum toxin effectively blocks the release of acetylcholine from motor nerve terminals. Thus, botulinum toxin injections are well established in the treatment of disorders in which patients are impaired by involuntary muscle contractions. A remarkable pain reduction was frequently observed in these patients, and in vitro studies showed that botulinum toxin reduces not only the release of acetylcholine, but also the release of neuropeptides involved in pain perception. It was therefore hypothesized that botulinum toxin may help patients with pain not caused by muscular contractions, such as migraine or chronic daily headache, which includes chronic migraine. So far, the results of randomized, double-blind, placebo controlled trials on botulinum toxin in a total of 2,612 patients with migraine or with chronic daily headache were published. A superiority of botulinum toxin compared with placebo injections could not clearly be confirmed in any of the studies. One hypothesis derived from these results was that subgroups of patients with migraine can be defined in whom botulinum toxin may be efficacious. This hypothesis awaits confirmation. Interestingly, the efficacy of both botulinum toxin and placebo injections was found to be significant and similar to the efficacy of established oral migraine treatment. This finding may help explain the enthusiasm that followed the first open-label use of botulinum in patients with migraine. Drug Dev Res 68:397,402, 2007. © 2008 Wiley-Liss, Inc. [source]


Cannabinoid,vanilloid receptor interactions in pain signaling

JOURNAL OF NEUROCHEMISTRY, Issue 2003
V. Di Marzo
Agents that activate cannabinoid CB1 receptors for marijuana's active principal, THC, or vanilloid VR1 receptors for red chilli peppers' pungent ingredient, capsaicin, modulate pain perception. Stimulation of presynaptic CB1 leads to inhibition of glutamate release in the spinal cord, whereas VR1 stimulation causes release of substance P and CGRP from DRG neurons. VR1 undergoes rapid desensitization by its agonists, which makes VR1-expressing neurons insensitive to subsequent stimulation and results in analgesia. Thus, both CB1 and VR1, which are coexpressed in several spinal and DRG neurons, are targets for analgesic drug development. CB1 and VR1 also share endogenous agonists, namely anandamide, NADA and some of their analogs, and may be regarded as metabotropic and ionotropic receptors for the same family of mediators, with opposing roles in pain perception. The development of ,hybrid' CB1/VR1 agonists as potent analgesics and the functional relationships between CB1 and VR1 in sensory neurons will be discussed. [source]


Nonimmersive Virtual Reality Mirror Visual Feedback Therapy and Its Application for the Treatment of Complex Regional Pain Syndrome: An Open-Label Pilot Study

PAIN MEDICINE, Issue 4 2010
Kenji Sato MD
Abstract Objective., Chronic pain conditions such as phantom limb pain and complex regional pain syndrome are difficult to treat, and traditional pharmacological treatment and invasive neural block are not always effective. Plasticity in the central nervous system occurs in these conditions and may be associated with pain. Mirror visual feedback therapy aims to restore normal cortical organization and is applied in the treatment of chronic pain conditions. However, not all patients benefit from this treatment. Virtual reality technology is increasingly attracting attention for medical application, including as an analgesic modality. An advanced mirror visual feedback system with virtual reality technology may have increased analgesic efficacy and benefit a wider patient population. In this preliminary work, we developed a virtual reality mirror visual feedback system and applied it to the treatment of complex regional pain syndrome. Design., A small open-label case series. Five patients with complex regional pain syndrome received virtual reality mirror visual feedback therapy once a week for five to eight sessions on an outpatient basis. Patients were monitored for continued medication use and pain intensity. Results., Four of the five patients showed >50% reduction in pain intensity. Two of these patients ended their visits to our pain clinic after five sessions. Conclusion., Our results indicate that virtual reality mirror visual feedback therapy is a promising alternative treatment for complex regional pain syndrome. Further studies are necessary before concluding that analgesia provided from virtual reality mirror visual feedback therapy is the result of reversing maladaptive changes in pain perception. [source]


The Unequal Burden of Pain: Confronting Racial and Ethnic Disparities in Pain

PAIN MEDICINE, Issue 3 2003
Carmen R. Green MD
ABSTRACT context. Pain has significant socioeconomic, health, and quality-of-life implications. Racial- and ethnic-based differences in the pain care experience have been described. Racial and ethnic minorities tend to be undertreated for pain when compared with non-Hispanic Whites. objectives. To provide health care providers, researchers, health care policy analysts, government officials, patients, and the general public with pertinent evidence regarding differences in pain perception, assessment, and treatment for racial and ethnic minorities. Evidence is provided for racial- and ethnic-based differences in pain care across different types of pain (i.e., experimental pain, acute postoperative pain, cancer pain, chronic non-malignant pain) and settings (i.e., emergency department). Pertinent literature on patient, health care provider, and health care system factors that contribute to racial and ethnic disparities in pain treatment are provided. evidence. A selective literature review was performed by experts in pain. The experts developed abstracts with relevant citations on racial and ethnic disparities within their specific areas of expertise. Scientific evidence was given precedence over anecdotal experience. The abstracts were compiled for this manuscript. The draft manuscript was made available to the experts for comment and review prior to submission for publication. conclusions. Consistent with the Institute of Medicine's report on health care disparities, racial and ethnic disparities in pain perception, assessment, and treatment were found in all settings (i.e., postoperative, emergency room) and across all types of pain (i.e., acute, cancer, chronic nonmalignant, and experimental). The literature suggests that the sources of pain disparities among racial and ethnic minorities are complex, involving patient (e.g., patient/health care provider communication, attitudes), health care provider (e.g., decision making), and health care system (e.g., access to pain medication) factors. There is a need for improved training for health care providers and educational interventions for patients. A comprehensive pain research agenda is necessary to address pain disparities among racial and ethnic minorities. [source]


Chest pain is inversely associated with blood pressure during exercise among individuals being assessed for coronary heart disease

PSYCHOPHYSIOLOGY, Issue 2 2007
Blaine Ditto
Abstract Acute and chronic increases in blood pressure have been related to decreases in pain perception. This phenomenon has been studied primarily using acute experimental pain stimuli. To extend the literature to naturalistic pain and in particular the problem of silent cardiac ischemia, this study examined the relationship between blood pressure and chest pain during exercise stress testing. Nine hundred seven (425 men, 482 women) individuals undergoing exercise stress testing for diagnosis of possible myocardial ischemia completed the McGill Pain Questionnaire (MPQ) immediately afterward and other questionnaires before and after testing. Blood pressure was measured before, during, and after exercise. Systolic blood pressure at the end of exercise was inversely related to a number of measures of pain such as total score on the MPQ. The relationship could not be explained by individual differences in exercise duration, medication use, sex, or other measured variable. In sum, the inverse relationship between blood pressure and sensitivity to pain that has been observed in other populations in experimental and naturalistic conditions was observed for chest pain during exercise. Blood pressure may contribute to episodes of silent ischemia. [source]