Desloratadine (Sch34117) is a long-acting piperidine derivate with selective H1 antihistaminergic and non-sedating properties. Desloratadine diminishes the typical histaminergic effects on H1-receptors in bronchial smooth muscle, capillaries and gastrointestinal smooth muscle, including vasodilation, bronchoconstriction, increased vascular permeability, pain, itching and spasmodic contractions of gastrointestinal smooth muscle. Desloratadine is used to provide symptomatic relieve of allergic symptoms.

H1 receptor:51 nM

Desloratadine抑制小鼠体内组胺诱导的足肿胀,ED50为0.15 mg/kg.去氯雷他定（1 mg/mL,3 mg/mL和10 mg/mL）在体内诱导豚鼠的剂量依赖性和持久散瞳.Desloratadine抑制豚鼠体内组胺侵袭上呼吸道引起的血管通透性增加,ED50为0.9 μg.5 mg/kg Desloratadine通过破坏清醒小鼠中的血脑屏障而引起抑制氧化震颤素诱导的震颤.

Desloratadine是卡巴胆碱诱导的离体兔虹膜平滑肌收缩的竞争性拮抗剂,pA2为6.67。 D去氯雷他定以0.87 nM的Ki值结合人H1受体,取代氚标记的美吡拉敏。Desloratadine在竞争性结合研究中,比西替利嗪,依巴斯汀,非索非那定和氯雷他定分别有效52,57,194以及153倍。0.1 μM到10 μM Desloratadine也显示抑制血小板活化因子诱导的嗜酸性粒细胞趋化性和TNF-α诱导的嗜酸性粒细胞在患有变应性鼻炎或变应性哮喘的患者中的嗜酸性粒细胞粘附。0.1 μM-10 μM Desloratadine剂量依赖性来自人嗜碱性粒细胞的IL-3和PMA活化的嗜碱性粒细胞的IL-13分泌。10 μM Desloratadine在培养的嗜碱粒细胞中,预处理导致培养的嗜碱性粒细胞中抗-IgE活化积累的IL-4信息减少约80％。[3H]Desloratadine以1.1 nM的Kd结合CHO细胞中表达的人组胺H1受体。100 nM到10 μM Desloratadine抑制IgE介导的和非IgE介导的人嗜碱粒细胞中细胞因子IL-4 和IL-13的产生。300 nM到100 μM Desloratadine抑制IgE介导的和非IgE介导的组胺从人周边血液嗜碱性粒细胞的释放。