scholarly journals A 5-HT Antagonist (UP 26-91) versus Codeine and Placebo in a Human Experimental Pain Study

2000 ◽  
Vol 5 (2) ◽  
pp. 135-140 ◽  
Author(s):  
Lars Arendt-Nielsen ◽  
Poul Pedersen ◽  
Lars Poulsen ◽  
Ole Kæseler Andersen ◽  
Peter Bjerring ◽  
...  

BACKGROUND: This double-blind, randomized, crossover study compared the potential analgesic effect of the serotonin receptor antagonist UP 26-91 (50 mg, 150 mg and 300 mg) with that of codeine (100 mg) and placebo by use of different human experimental pain models.SUBJECTS AND METHODS: In experiment 1, pain detection and tolerance thresholds to heat, pressure and pain ratings during the cold pressor test were measured. In experiment 2, the pain threshold to single and repetitive (temporal summation) electrical sural nerve stimulation, and the pain intensity on a visual analogue scale to supra pain threshold electrical stimulation (stimulus-response-function) were measured. Tests were performed before, and 1, 2 and 6 h after drug administration.RESULTS: UP 26-91 did not show a marked effect on the experimental pain tests. Most of the variables tended to show a better effect from codeine than from placebo, but statistical significance for peak pain was only reached during the cold pressor test (P=0.011).CONCLUSIONS: In the present doses, the serotonin antagonist UP 26-91 had no effect on the experimental pain models applied.

2010 ◽  
Vol 1 (3) ◽  
pp. 143-148 ◽  
Author(s):  
Thomas P. Enggaard ◽  
Søren S. Mikkelsen ◽  
Stine T. Zwisler ◽  
Niels A. Klitgaard ◽  
Søren H. Sindrup

AbstractBackgroundThe antidepressant drugs imipramine and venlafaxine relieve clinical neuropathic pain and have been shown to increase pain thresholds in healthy volunteers during repetitive electrical sural nerve stimulation causing temporal pain summation, whereas pain during the cold pressor test is unaltered by these drugs. If this pattern of effect in experimental pain models reflects potential efficacy in clinical neuropathic pain, the pain summation model may potentially be used to identify new drugs for such pain conditions. Gabapentinoids are evidence-based treatments of clinical neuropathic pain and could contribute with additional knowledge of the usefulness of the pain summation model.The aim of this studyTo test the analgesic effect of the gabapentinoid gabapentin in a sural nerve stimulation pain model including temporal pain summation and the cold pressor test.Method18 healthy volunteers completed a randomized, double-blind, cross-over trial with medication of 600 mg gabapentin orally dosed 3 times over 24 h against placebo. Pain tests were performed before and 24 h after medication including pain detection and tolerance to single sural nerve stimulation and pain summation threshold to repetitive stimulation (3 Hz). Peak pain intensity and discomfort were rated during a cold pressor test.ResultsCompared to placebo, gabapentin had a highly significant effect on the threshold of pain summation to repetitive electrical sural nerve stimulation (P = 0.009). Gabapentin significantly increased the pain tolerance threshold to single electrical sural nerve stimulation (P = 0.04), whereas the pain detection threshold to single electrical sural nerve stimulation tended to be increased (P = 0.06). No significant differences were found on pain ratings during the cold pressor test.ConclusionGabapentin had a selective hypoalgesic effect in a human experimental pain model of temporal pain summation and the results lend further support to the usefulness of the pain summation model to identify drugs for neuropathic pain.


Author(s):  
Simiat Olanike Elias ◽  
Irene Yewande Bamgbade

Adrenomedullin is a potent vasodilator with established cardio-protective potentials when the body is exposed to stress. Sympathetic autonomic stress can lead to systolic (SBP) and diastolic blood pressure (DBP) reactivity which is a predictor of stroke. This study was to determine the effect of Adrenomedullin on cardiovascular response to sympathetic autonomic stress using the Cold Pressor Test in normotensive (NT) and hypertensive (HT) adults. Cardiovascular response to the CPT was measured among 30 NT and 30 HT participants, via blood pressure and heart rate before and after exposure to the cold pressor test (CPT). Plasma Adrenomedullin (ADM) was also determined by means of ELISA. Data were expressed as mean±S.E.M and statistical significance was accepted at 95% confidence interval. Exposure to CPT led to significant increases in SBP and DBP in both NT and HT participants with greater effect in HT (p<0.0001). Plasma Adrenomedullin was significantly higher among the NT but the difference on effect of response to CPT in both groups of participants was not significant. There was a negative and insignificant correlation between the ADM level and change in SBP and DBP among the NT participants but a positive and insignificant correlation with both SBP and DBP among the HT participants. We conclude that plasma Adrenomedullin may prevent the development of hypertension in black individuals.


2007 ◽  
Vol 293 (4) ◽  
pp. R1711-R1716 ◽  
Author(s):  
Kent Stening ◽  
Olle Eriksson ◽  
LisKarin Wahren ◽  
Göran Berg ◽  
Mats Hammar ◽  
...  

The role of gonadal hormones on pain sensations was investigated in normally menstruating women ( n = 16) using the cold pressor test. Tolerance time, pain threshold, and pain intensity were examined once a week during a 4-wk period, and serum concentrations of 17β-estradiol and progesterone were determined at each test session, which were classified into the early follicular phase, late follicular phase, early luteal phase, and late luteal phase, as determined by the first day of menses and the actual hormone levels recorded. A group of men ( n = 10) of the same age interval was examined for comparison. The data show that pain threshold was reduced during the late luteal phase compared with the late follicular phase, and hormone analyses showed significant positive correlation between the progesterone concentration and lowered pain threshold and increasing pain intensity. Hormone analysis also showed an interaction between S-estradiol and S-progesterone on pain intensity, demonstrating that the increased perceived pain intensity that was associated with high progesterone concentrations was significantly reduced with increasing levels of estradiol. While no statistically significant sex differences in pain measurements were found, women displayed much more pronounced, and statistically significant, session-to-session effects than men, with increased pain threshold and decreased pain intensity with each test session. Hence, these data suggest that the changes in the serum concentration of gonadal hormones that occur during the menstrual cycle influence pain sensations elicited by noxious tonic cold stimulation and show that adaptation to the cold pressor test may be sex dependent.


2012 ◽  
Vol 17 (2) ◽  
pp. 98-102 ◽  
Author(s):  
Gwyn N Lewis ◽  
Heales Luke ◽  
David A Rice ◽  
Keith Rome ◽  
Peter J McNair

BACKGROUND: Conditioned pain modulation paradigms are often used to assess the diffuse noxious inhibitory control (DNIC) system. DNICs provide one of the main supraspinal pain inhibitory pathways and are impaired in several chronic pain populations. Only one previous study has examined the psychometric properties of the conditioned pain modulation technique and this study did not evaluate intersession reliability.OBJECTIVES: To evaluate and compare the intra- and intersession reliability of two conditioned pain modulation paradigms using different conditioning stimuli, and to determine the time course of conditioned pain inhibition following stimulus removal.METHODS: An electronic pressure transducer was used to determine the pressure-pain threshold at the knee during painful conditioning of the opposite hand using the ischemic arm test and the cold pressor test. Assessments were completed twice on one day and repeated once approximately three days later.RESULTS: The two conditioning stimuli resulted in a similar increase in the pressure-pain threshold at the knee, reflecting presumed activation of the DNIC system. Intrasession intraclass correlation coefficients for the cold pressor (0.85) and ischemic arm tests (0.75) were excellent. The intersession intraclass correlation coefficient for the cold pressor test was good (0.66) but was poor for the ischemic arm test (−0.4). Inhibition of the pressure-pain threshold remained significant at 10 min following conditioning, but returned to baseline by 15 min.CONCLUSIONS: Within-session reliability of DNIC assessment using conditioned pain modulation paradigms was excellent, but the applicability of assessing pain modulation over multiple sessions was influenced by the conditioning stimulus. The cold pressor test was the superior technique.


2016 ◽  
Vol 14 (4) ◽  
Author(s):  
Marcelo Coertjens

Introdução: A crioterapia é um recurso que diminui a temperatura corporal local com finalidades terapêuticas. Uma importante repercussão é a vasoconstrição local, que seria o desencadeador de um possível aumento na pressão arterial (PA). Entretanto, não existem trabalhos que comprovem essa suposição. Nossa hipótese é que os resultados das pesquisas de Cold Pressor Test (CPT) avaliando PA acabaram historicamente fundamentando as precauções da crioterapia em relação a pacientes hipertensos. Objetivo: Realizar uma revisão de literatura a respeito das pesquisas que sustentam a precaução da crioterapia em indivíduos hipertensos e verificar sua relação com estudos que utilizaram o CPT. Material e métodos: Trata-se de uma revisão de literatura que utilizou as bases de dados online Medline, Scielo, Lilacs e Google Acadêmico para a realização da pesquisa. Resultado: Apesar de não serem unânimes, diversas pesquisas que utilizaram o CPT encontraram significativos aumentos da atividade nervosa simpática muscular e da PA em normotensos e hipertensos, entretanto não encontramos estudos que tenham comprovado respostas significativas de PA com o uso da crioterapia, principalmente, em hipertensos. Conclusão: Não existem evidências científicas que comprovem a precaução da crioterapia em indivíduos hipertensos. Além disso, os estudos com CPT não são unânimes em relação aos aumentos pressóricos em indivíduos normotensos e hipertensos.Palavras-chave: crioterapia, hemodinâmica, hipertensão, pressão arterial. 


Author(s):  
Guillaume Lamotte ◽  
Christopher J. Boes ◽  
Phillip A. Low ◽  
Elizabeth A. Coon

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Morten Pallisgaard Støve ◽  
Rogerio Pessoto Hirata ◽  
Thorvaldur Skuli Palsson

Abstract Objectives The effect of stretching on joint range of motion is well documented, and although sensory perception has significance for changes in the tolerance to stretch following stretching the underlining mechanisms responsible for these changes is insufficiently understood. The aim of this study was to examine the influence of endogenous pain inhibitory mechanisms on stretch tolerance and to investigate the relationship between range of motion and changes in pain sensitivity. Methods Nineteen healthy males participated in this randomized, repeated-measures crossover study, conducted on 2 separate days. Knee extension range of motion, passive resistive torque, and pressure pain thresholds were recorded before, after, and 10 min after each of four experimental conditions; (i) Exercise-induced hypoalgesia, (ii) two bouts of static stretching, (iii) resting, and (iv) a remote, painful stimulus induced by the cold pressor test. Results Exercise-induced hypoalgesia and cold pressor test caused an increase in range of motion (p<0.034) and pressure pain thresholds (p<0.027). Moderate correlations in pressure pain thresholds were found between exercise-induced hypoalgesia and static stretch (Rho>0.507, p=0.01) and exercise-induced hypoalgesia and the cold pressor test (Rho=0.562, p=0.01). A weak correlation in pressure pain thresholds and changes in range of motion were found following the cold pressor test (Rho=0.460, p=0.047). However, a potential carryover hypoalgesic effect may have affected the results of the static stretch. Conclusions These results suggest that stretch tolerance may be linked with endogenous modulation of pain. Present results suggest, that stretch tolerance may merely be a marker for pain sensitivity which may have clinical significance given that stretching is often prescribed in the rehabilitation of different musculoskeletal pain conditions where reduced endogenous pain inhibition is frequently seen.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kilin Shi ◽  
Tobias Steigleder ◽  
Sven Schellenberger ◽  
Fabian Michler ◽  
Anke Malessa ◽  
...  

AbstractContactless measurement of heart rate variability (HRV), which reflects changes of the autonomic nervous system (ANS) and provides crucial information on the health status of a person, would provide great benefits for both patients and doctors during prevention and aftercare. However, gold standard devices to record the HRV, such as the electrocardiograph, have the common disadvantage that they need permanent skin contact with the patient. Being connected to a monitoring device by cable reduces the mobility, comfort, and compliance by patients. Here, we present a contactless approach using a 24 GHz Six-Port-based radar system and an LSTM network for radar heart sound segmentation. The best scores are obtained using a two-layer bidirectional LSTM architecture. To verify the performance of the proposed system not only in a static measurement scenario but also during a dynamic change of HRV parameters, a stimulation of the ANS through a cold pressor test is integrated in the study design. A total of 638 minutes of data is gathered from 25 test subjects and is analysed extensively. High F-scores of over 95% are achieved for heartbeat detection. HRV indices such as HF norm are extracted with relative errors around 5%. Our proposed approach is capable to perform contactless and convenient HRV monitoring and is therefore suitable for long-term recordings in clinical environments and home-care scenarios.


Sign in / Sign up

Export Citation Format

Share Document