Histamine Receptor Antagonist

Amitriptyline is an orally active tricyclic antidepressant (TCA). Amitriptyline mainly exerts its antidepressant effect by blocking SERT (K_i = 3.45 nM) and NET (K_i = 13.3 nM), thereby increasing the concentrations of 5-hydroxytryptamine (5-HT) and norepinephrine (NE) in the synaptic cleft. Amitriptyline is also an agonist at α2A and TrkA/TrkB receptors, thereby exerting analgesic and neurotrophic activities (inhibiting cell apoptosis). Amitriptyline can reduce inflammation, angiogenesis and fibrosis. Amitriptyline binds to DAT (with K_i = 2.58 μM). Amitriptyline has high affinity for a series of receptors and can antagonize muscarinic cholinergic receptors (M1/M2/M3/M4/M5 receptors) (K_i = 11-24 nM), H1 receptors (K_i = 0.5-1.1 nM), adrenergic α1 receptors (K_i = 4.4 nM), etc., resulting in a series of side effects. Amitriptyline can block sodium channels and hERG potassium channel (IC₅₀ = 4.78 μM) and it has cardiotoxicity.

Trazodone (AF-1161 free base) is a triazolopyridine derivative that belongs to the class of serotonin receptor antagonists and reuptake inhibitors (SARIs). Trazodone has anti-depressant and anti-insomnious activity. Trazodone exerts antagonistic properties against a1- and a2-adrenergic receptors and histamine H1 receptors, with minimal anticholinergic effects.

Promethazine is an orally active histamine receptor antagonist. Promethazine is first-generation antihistamine of the phenothiazine family, shows strong sedative and weak antipsychotic effects.

Levomepromazine (Methotrimeprazine) is an orally active antipsychotic compound and Ca²⁺ release inducer. Levomepromazine inhibits SERCA pump and induces an increase in cytoplasmic Ca²⁺ levels. Levomepromazine has antagonistic effects on a variety of neurotransmitter receptors, including dopamine, cholinergic, serotonin, and histamine receptors. Levomepromazine can induce adaptive ER stress and autophagy. In addition, Levomepromazine has antiviral, anti-inflammatory, neuroprotective and analgesic, sedative and anti-injurious activities. Levomepromazine can be used in the study psychiatric disorders and relieving nausea and vomiting.

Chlorpheniramine is a H1 antihistamines commonly used in allergic diseases research.

Trazodone hydrochloride (AF-1161) is a triazolopyridine derivative that belongs to the class of serotonin receptor antagonists and reuptake inhibitors (SARIs). Trazodone hydrochloride has anti-depressant and anti-insomnious activity. Trazodone hydrochloride exerts antagonistic properties against a1- and a2-adrenergic receptors and histamine H1 receptors, with minimal anticholinergic effects.

Mizolastine is an orally active, high affinity and specific peripheral histamine H1 receptor antagonist (second generation antihistamine). Mizolastine effectively inhibits mRNA expression of VEGF165, VEGF120, TNF-α and KC. Mizolastine can be used in studies of allergic rhinitis and chronic idiopathic urticarial.

Adriforant hydrochloride (PF-3893787 hydrochloride) is a novel histamine H4 receptor antagonist binding affinity (K_i=2.4 nM) and is also a functional (K_i=1.56 nM) antagonist.

Latrepirdine dihydrochloride is a neuroactive compound with antagonist activity at histaminergic, α-adrenergic, and serotonergic receptors. Latrepirdine stimulates amyloid precursor protein (APP) catabolism and amyloid-β (Aβ) secretion.

Samelisant (SUVN-G3031) is a potent and selective histamine H3 receptor (H3R) inverse agonist with good brain penetration and oral bioavailability. Samelisant has a similar binding affinity towards human (hH3R; K_i=8.7 nM) and rat (rH3R;K_i=9.8 nM) H3R indicating no inter-species differences. Samelisant can be used for the research of sleep-related disorders.

Mequitazine is a potent, and long-acting histamine H₁ antagonist.

Tecastemizole (Norastemizole), a major metabolite of Astemizole, is a potent and selective H1 receptor antagonist. Tecastemizole shows anti-inflammatory activities.

Lafutidine (FRG-8813) is a histamine H2-receptor antagonist (H₂RA), with proven gastric mucosal protective effects. Lafutidine can be used for the research of gastroesophageal reflux disease.

Terfenadine (Standard) is the analytical standard of Terfenadine. This product is intended for research and analytical applications. Terfenadine ((±)-Terfenadine) is a potent open-channel blocker of hERG with an IC50 of 204 nM. Terfenadine, an H1 histamine receptor antagonist, acts as a potent apoptosis inducer in melanoma cells through modulation of Ca2+ homeostasis. Terfenadine induces ROS-dependent apoptosis, simultaneously activates Caspase-4, -2, -9.

Triprolidine is an orally active H1R Antagonist antagonist. Triprolidine has the function of spinal cord motor and sensory block. Triprolidine can be used for the research of allergic rhinitis.

Conessine is an orally active and BBB-penetrable selective histamine H3 receptor antagonist. The pK_i values of Conessine for rat and human H3 receptors are 7.61 and 8.27, respectively. Conessine is an inhibitor of the multidrug efflux pump system in Pseudomonas aeruginosa and can enhance the activity of antibiotics. Conessine has antimalarial activity. Conessine can also be used in the research of muscle atrophy.

Methapyrilene is a histamine antagonist, a pyridine chemical with anticholinergic activity. Methapyrilene can cause target organ-specific epigenetic alterations, such as a decrease in DNA methylation levels. Methapyrilene induces hepatocellular carcinoma in rats.

Mebhydrolin is a specific histamine H₁ receptor antagonist.

Dimethindene maleate is a selective histamine H1 antagonist with antihistamine effects. Dimethindene maleate can be used for the research of hypersensitivity reactions.

Levocetirizine (dihydrochloride) (Standard) is the analytical standard of Levocetirizine (dihydrochloride). This product is intended for research and analytical applications. Levocetirizine dihydrochloride ((R)-Cetirizine dihydrochloride) is a third-generation peripheral H1-receptor antagonist. Levocetirizine dihydrochloride is an antihistaminic agent which is the R-enantiomer of Cetirizine. Levocetirizine dihydrochloride has a higher affinity for the histamine H1-receptor than (S)-Cetirizine and can effectively treat allergic rhinitis and chronic idiopathic urticaria.