Disease relevance of Pain Threshold

• RESULTS: Compared with placebo, melatonin taken for two weeks significantly decreased mean abdominal pain score (2.35 v 0.70; p<0.001) and increased mean rectal pain threshold (8.9 v -1.2 mm Hg; p<0.01) [1].
• On-going discharges and lowered response thresholds to heat in these units after topical application of capsaicin correlates with background pain as well as lowered pain thresholds to heat of the affected skin (primary hyperalgesia) [2].
• Altered heat pain thresholds and cerebral event-related potentials following painful CO2 laser stimulation in subjects with fibromyalgia syndrome [3].
• RESULTS: Butyrate enemas (40 mM twice daily for 14 days) decreased colonic pain thresholds in control rats; they did not reduce the TNBS-induced hypersensitivity, but on the contrary increased its duration (without modifying the inflammation score) [4].
• Pressure pain thresholds in patients with craniomandibular disorders before and after treatment with acupuncture and occlusal splint therapy: a controlled clinical study [5].

Psychiatry related information on Pain Threshold

• Furthermore, since the oxytocin antagonist did not significantly alter response latency on the hot-plate test, it is unlikely that endogenous oxytocin exerts a tonic effect on the pain threshold in rats [6].
• REM sleep deprivation (REMSD) decreased the basal pain threshold and abolished the analgesic effect of phosphoramidon [7].
• The objective of this study was to test the effect of melatonin on thermal pain threshold in female patients with eating disorders [8].
• They had the characteristic clinical features of an abnormally high pain threshold, and mental retardation; in addition their clinical course was marked by the occurrence of early onset renal disease with recurrent microhematuria and proteinuria and frequent observations of increased serum creatinine and blood urea levels [9].
• During assessment, 178 patients with TMJPD were given a pressure pain threshold and tolerance task and completed the Basic Personality Inventory, the Illness Behavior Questionnaire, the Multidimensional Health Locus of Control, the Perceived Stress Scale, and the Ways of Coping Checklist [10].

High impact information on Pain Threshold

• Ketamine (NMDA receptor antagonist) or saline (vehicle) was given intravenously either prior to or following acid infusion, and pain thresholds were measured for the following 120 minutes [11].
• METHODS: Brain (15)O-water positron emission tomography was performed in 15 right-handed healthy volunteers during baseline and distal gastric distentions to 10 mm Hg, 20 mm Hg, threshold pain, and moderate pain [12].
• The GIRK2-null mutation reduced the "pain" threshold in male but not in female mice, effectively eliminating the sex differences in pain threshold [13].
• Compared with female WT mice, male WT mice exhibited higher pain thresholds and enhanced opioid (morphine) and alpha(2)-adrenergic (clonidine) receptor-induced antinociception in a spinal reflex test [13].
• We now show that mice that cannot produce these peptides display no significant pain responses following formalin injection and have an increased pain threshold in the hotplate test [14].

Chemical compound and disease context of Pain Threshold

• We propose that in diabetes, generally, the pain threshold is adequately maintained, despite the antagonistic effect of glucose, partly due to a compensatory increased secretion of endogenous opioid peptides [15].
• Hydroxychloroquine and pain thresholds [16].
• As a functional corollary to alterations in neurochemical parameters, we observed significant disulfiram-induced increases in pain thresholds, potentiated by capsaicin treatment [17].
• OBJECTIVES: The purpose of this study was to test whether cutaneous thermal pain thresholds are related to anginal pain perception [18].
• METHODS: This was a randomized, double-blind, placebo-controlled study designed to compare the antihyperalgesic efficacy of topical (65 mg) and oral (93 mg) diclofenac via estimates of mechanical pain thresholds obtained at the site of induced inflammation with von Frey hairs [19].

Biological context of Pain Threshold

• The present study examined heat pain thresholds and cerebral event-related potentials following CO2 laser stimulation in 10 subjects with FS and 10 age-matched control volunteers [3].
• In this study we have confirmed the anti-inflammatory effect of dexamethasone and linked this to central changes in gene expression relevant to the development of altered pain thresholds following intraplantar FCA [20].
• A CO2 laser beam, which is useful for pure nociceptive stimulation, was used for recording pain-related somatosensory evoked potentials (pain SEPs) and for measuring pain threshold and reaction time (RT) [21].
• The aim of the study was to investigate whether the altered physiological profiles were modified by utilising tizanidine, an alpha 2 adrenergic receptor agonist which is capable of affecting faecal and urinary excretion, rectal temperature, pain threshold levels and salivation [22].
• We conclude there is no detectable structural basis for the reduction in nerve conduction velocity, pain threshold or blood flow, observed in the streptozotocin diabetic rat [23].

Anatomical context of Pain Threshold

• Both nociceptor response thresholds and pain thresholds were lowered for heat from 45 to 35 degrees C. A newly developed weak response to stroking the skin in two units after capsaicin was accompanied by faint pain [2].
• Quantitative sensory testing (pressure and thermal pain thresholds, the brachial plexus provocation test), the sympathetic vasoconstrictor reflex and psychological distress (GHQ-28) were prospectively measured in 76 whiplash subjects within 1 month of injury and then 2, 3 and 6 months post-injury [24].
• Sex differences in temporal characteristics of DNIC were investigated by measuring pressure pain thresholds (PPTs) over time in the trapezius muscles (local pain areas) and the posterolateral neck muscles (referred pain areas) following repeated bilateral injection of hypertonic versus isotonic saline into both trapezius muscles [25].
• PRES baroreceptor manipulation had no significant effect on thermal pain threshold for either group [26].
• In the temporal muscle, none of the test substances induced more pain than saline, but substance-P with bradykinin lowered the pressure pain threshold by 18% (p less than 0.02) [27].

Gene context of Pain Threshold

• No overt behavioral differences were apparent between Folh1-/- mice and wild-type littermates, with respect to their overall performance in locomotion, coordination, pain threshold, cognition and psychiatric behavioral paradigms [28].
• Peripheral CRF reduced pain threshold to colonic distention and increased colonic motility in humans [29].
• Despite the increase in CGRP in GDNF-treated rats, there was no increase in thermal or mechanical pain sensitivity, while NGF-treated animals showed significant decreases in pain thresholds [30].
• These studies demonstrate that, in contrast to the highly significant role for Nav1.7 in determining inflammatory pain thresholds, the development of neuropathic pain does not require the presence of either Nav1.7 or Nav1.8 alone or in combination [31].
• Double knockouts of both Nav1.7 and Nav1.8 also develop normal levels of neuropathic pain, despite a lack of inflammatory pain symptoms and altered mechanical and thermal acute pain thresholds [31].

Analytical, diagnostic and therapeutic context of Pain Threshold

• Epinephrine caused a slight increase in subjective pain due to electrical stimulation and a decrease in heat pain threshold, which was larger on capsaicin-treated than on normal skin [32].
• Intravenous injection of acetylsalicylic acid increased only the RIII,Cu threshold and relative pain threshold [33].
• Seven electrical stimuli spaced between individually determined pain threshold and tolerance values were delivered in random sequence 6 times before and after double-blind intravenous infusions of placebo, 0.11 mg/kg diazepam, 0.66 microgram/kg fentanyl or a combination of the diazepam and fentanyl doses [34].
• I.c.v. treatment with heparin, an IP(3) receptor antagonist, prevented the increase of pain threshold induced by the investigated compound, analgesia that was restored by co-administration of D-myo-inositol [35].
• The results of these studies indicate that streptozotocin-induced diabetic animals have a significantly higher pain threshold (P less than 0.01) than the control groups [36].

References