It has long been established that histamine plays a role as a mediator of inflammation. From numerous studies, it has been well known that the amine has many pharmacological actions on a variety of organs. To evaluate the role of histamine in pain perception, we generated HDC knockout mice using a gene targeting method. Histamine is a hydrophilic autacoid, and in most tissues it is stored and s...

Introduction: Pain research using animal models is related to ethical concerns, so invertebrates and insects have been recommended by researchers. In the present study, the nociceptive and antinociceptive effects of capsaicin, aspirin, morphine and chili extract were examined using fruit fly (Drosophila melanogaster) as an alternative for rodent pain model. Methods: Stage 3 of larvae and ad...

In this article, we demonstrate assays to study thermal nociception in Drosophila larvae. One assay involves spatially-restricted (local) stimulation of thermal nociceptors while the second involves a wholesale (global) activation of most or all such neurons. Together, these techniques allow visualization and quantification of the behavioral functions of Drosophila nociceptive sensory neurons. ...

The existence of neural opioid-mediated networks that are specific for the modulation of nociception is well established. Parallel non-opioid pathways exist, but their underlying physiology is little known. We now report that oxytocin administered intraperitoneally to rats, and intraperitoneally or intracisternally to mice has an anti-nociceptive effect, which is related to the activation of de...

Mechanical hyperalgesia is a clinically-relevant form of pain sensitization that develops through largely unknown mechanisms. TRPA1, a Transient Receptor Potential ion channel, is a sensor of pungent chemicals that may play a role in acute noxious mechanosensation and cold thermosensation. We have developed a specific small molecule TRPA1 inhibitor (AP18) that can reduce cinnameldehyde-induced ...

Background Persistent stimulation of nociceptors results in sensitization of nociceptive sensory neurons, which is associated with hyperalgesia and allodynia. The release of NO and subsequent synthesis of cGMP in the spinal cord are involved in this process. cGMP-dependent protein kinase I (PKG-I) has been suggested to act as a downstream target of cGMP, but its exact role in nociception hadn't...

The Neuropeptide FF receptor family contains two subtypes, NPFF1 and NPFF2 (provisional nomenclature [12]), which exhibit high affinities for neuropeptide (NPFF, O15130) RFamide related peptides (RFRP: precursor gene symbol NPVF, Q9HCQ7). is broadly distributed in the central nervous system with highest levels found limbic hypothalamus. present density superficial layers of mammalian spinal cor...

In this study, we aimed to investigate the peripheral antinociception effects of specificphosphodiesterase 5 (PDE-5) inhibitor vardenafil on carrageenan-induced nociception in rats,and the role of calcium besides the L-arginine- nitric oxide (NO)- cyclic guanosine monophophate(cGMP) pathway in these effects. Hyperalgesia was induced by the intraplantar injection of 0.1mL fresh carrageenan solut...

Introduction: Pain as a complex process in the CNS has been extensively studied by many researchers. It has been found that pain is controlled by certain pathways in the CNS, one of most important of which is the descending noradrenergic system. The pathway begins with Locus Coeruleus (LC) nucleus and ends in the spinal cord. In this study, formalin test was used as a chemical and tonic pain...