Subjective pain (assessed by visual analogue scale in pain diary and by chairside archwire activation), periodontal status (assessed by periodontal clinical parameters), cytokines in gingival crevicular fluid (interleukin 1β, prostaglandin E<sub>2</sub>, substance P) and periodontopathic bacteria (Porphyromonas gingivalis and Treponema denticola) in supragingival plaque were assessed.
Intra-mPFC microinjection of naloxonazine (a mu-opioid receptor antagonist, 1 μg/0.25 μL) and AM251 (a cannabinoid CB1 receptor antagonist, 1 μg/0.25 μL) increased both phases of pain intensity.
The combination of both bradykinin and substance P reporter substances with specific enzyme inhibitors will shed more light on biochemical pathways in inflammatory processes and pain.
The primary aim of this study was to investigate the effects of the catechol-O-methyltransferaseVal158Met polymorphism on heat pain perception in a cohort of adults receiving daily opioid therapy for chronic pain.
Catechol-O-methyltransferase (COMT) enzyme has a major role in the adjustment of catechol-dependent functions, for example, cognition, cardiac function, and pain processing.
To analyze the association between the rs4680catechol-O-methyltransferaseVal158Met polymorphism and to determine the association of this polymorphism with clinical, psychological, and pain sensitivity variables in women with episodic or chronic migraine.
The endocannabinoid system involving the central nervous system (CNS), the human cannabinoid receptor 1 (CB1), is an important drug target and its variability has implications for disease susceptibility and altered drug and pain response.
The AA genotype of rs4680 or A_T_C_A/ A_T_C_A (rs6269_rs4633_ rs4818_rs4680) diplotype of COMT, combined with the AG genotype of OPRM1 A118G, showed significantly increased pressure pain threshold from butorphanol.
In chronic pain, the substance P (SP) neurokinin 1 receptor (NK<sub>1</sub>R) redistributes from the plasma membrane to acidified endosomes, where it signals to maintain pain.
Considering that the endocannabinoid system via CB1 receptors play a crucial role in pain modulation, we also assessed the possible role of the VH cannabinoid CB1 receptors in the functional interaction between minocycline and morphine in acute pain.
Various inhibitors of TRPV1, TRPV2, TRPM8, Piezo 2, ASICs, P2X, P2Y, B1, B2, AMPA, NMDA, mGlu, NK1 and CGRP receptors have shown high therapeutic value in experimental models of pain.
The association between COMTVal158Met polymorphism (rs4680) and the inter-individual differences in the response to opioid analgesic therapy was investigated in a cohort of 87 Italian paediatric patients receiving opioids for cancer pain (STOP Pain study).
Few associations replicated: morphine dose (mcg/kg) in African American children and ABCB1 rs1045642 (A allele, β = -9.30, 95% CI: -17.25 to -1.35, p = 0.02) and OPRM1 rs1799971 (G allele, β = 23.19, 95% CI: 3.27-43.11, p = 0.02); KCNJ6 rs2211843 and high pain in African American subjects (T allele, OR 2.08, 95% CI: 1.17-3.71, p = 0.01) and in congruent European Caucasian pain phenotypes; and COMTrs740603 for high pain in European Caucasian subjects (A allele, OR: 0.69, 95% CI: 0.48-0.99, p = 0.046).
The expression of TRPV1, ASIC-3, TDV8 encode ionic channels in RA and modulate the pain, likewise, the transcription factors in RA, such as TNFα, TGF-β1, IL-6, IL-10, IFN-γ, IL-1b, mTOR, p21, caspase 3, EDNRB, CGRP-CALCB, CGRP-CALCA, TAC1 are also directly involved in pain perception.
This double-blind, randomized, crossover study compared the local anesthetic effect of CTY-5339A versus 14% benzocaine alone by using 2 quantitative sensory threshold experimental pain paradigms on the maxillary gingiva: pin prick test pain intensity (PPT PI) and heat pain threshold (HPT).
Membrane metallo-endopeptidase (MME), also known as neprilysin (NEP), has been of interest for its role in neurodegeneration and pain due to its ability to degrade β-amyloid and substance-P, respectively.
Substance P is an eleven-amino acid neuropeptide (undecapeptide) with multiple effects on the gastrointestinal, cardiovascular, and urinary systems as well as complex central nervous system functions such as pain, learning, memory, and sexual homeostasis.
Moreover, genes associated with neuropathic pain including Maob, Grin2b/NMDAR2b, TrpV3, IL-6, Cacna1b/Ca<sub>v</sub>2.2, Itgam/Cd11b, Scn9a/Na<sub>v</sub>1.7, and Tac1 were all found to respond to the celecoxib loaded nanoemulsion during pain relief as compared to those animals that received drug-free vehicle.
Catechol-O-Methyltransferase (COMT) rs4680Val158Met Polymorphism is Associated With Widespread Pressure Pain Sensitivity and Depression in Women With Chronic, but not Episodic, Tension-Type Headache.
A possible mechanism for the effect of LLLT on fibromyalgia pain is via the antinociceptive signaling of substance P in muscle nociceptors, although the neuropeptide has been known as a neurotransmitter to facilitate pain signals in the spinal cord.