Histamine regulates arousal, circadian rhythms, and thermoregulation. Activation of H3 histamine receptors expressed by preoptic GABAergic neurons results in a decrease of their firing rate and hyperthermia. Here we report that an increase in the A-type K⁺ current in preoptic GABAergic neurons in response to activation of H3 histamine receptors results in decreased firing rate and hyperthermia ...

Toreforant is a potent and selective histamine H4 receptor (H4R) antagonist with a Ki at the human receptor of 8.4 ± 2.2 nM and excellent selectivity over other receptors including the other histamine receptors. The compound acts as an antagonist in all species tested and inhibits histamine-induced eosinophil shape change in vitro. Toreforant was anti-inflammatory in mouse models of asthma and ...

Several lines of evidence have indicated that many nuclei in the brain including preoptic nucleus, AV3V, subfornical organ, septal area and lateral hypothalamus are the targets of efferents from chemo-sensitive and pressure-sensitive systems. These areas may concern with regulation of fluid homeostasis. In the present study, intracerebroventricular injections were carried out in all experiments...

objective(s): the present study investigated the effects of microinjection of histamine and histamine h1, h2, and h3 receptor antagonists, chlorpheniramine, ranitidine and thioperamide, respectively into the primary somatosensory cortex (psc) on inflammatory pain.   material and methods: two stainless steel guide canulas were bilaterally implanted into the psc of anaesthetized rats. inflammator...

Glutamate and histamine are two inhibitory factors of appetite in central nervous system of birds. In the present study, interference effect of glutamate-histamine was evaluated. The broiler weighing 700±50gr, implanted sterile canule in right ventricle of their brine, were used. Animals were fasted for 24 hours before intra-ventricular micro-injection. After canule-implantation the birds were ...

1 Histamine produced dose-dependent contractile responses on both isolated perfused ear arteries and aortic strips of the rabbit. These responses were blocked by mepyramine and potentiated by both metiamide and dithiothreitol. 2 In the presence of maximum potentiation by metiamide, dithiothreitol still potentiated the contractile response to histamine of both preparations. 3 In the presence of ...

Histamine is one of the most important biogenic amines in medicine and biology but its role in allergy, autoimmune and neoplastic diseases has not yet been fully defined. The last few years have brought many discoveries concerning important modulatory effects of histamine and its receptors on basic mechanisms of the immunological processes. The role of histamine H1 and H2 receptors in immunomod...

Fexofenadine hydrochloride (FFH), chemically known as (±)-4-[1-hydroxy-4-[4-(hydroxydiphenylmethyl)-1-piperidinyl]butyl]-a,a-dimethyl benzene aceticacid hydrochloride [1] is a active metabolite of terfenadine and is a second-generation histamine H1-receptor antagonist in piperidine-class drugs. These drugs are used in the treatment of seasonal allergic rhinitis, chronic idiopathic urticaria etc...

Nicotine evokes pain in the skin and oral mucosa and excites a subpopulation of cutaneous nociceptors, but little is known about the central transmission of chemogenic pain. We have investigated the responses of lumbar spinal wide dynamic range (WDR)-type dorsal horn neurons to intracutaneous (ic) microinjection of nicotine in pentobarbital-anesthetized rats. Nearly all (97%) units responded to...