Abstract：
Urticaria is induced by the histamine released from mast cells which develops wheals (edema) as a visual feature. In clinical practice, second-generation histamine H1 -receptor blockers are routinely used as the first-line symptomatic treatment for urticaria. Nevertheless, not much research has directly examined the second-generation histamine H1-receptor blockers\' ability to reduce edema. In this study, we directly evaluated the anti-edematous activities of three second-generation histamine H1-receptor blockers available in the market (epinastine hydrochloride, cetirizine hydrochloride, and levocetirizine hydrochloride) using a λ-carrageenan-induced footpad edema model. One hour before the induction of edema with 1% λ -carrageenan injection, all second-generation histamine H1 -receptor blockers (5, 10, 50 and 100 mg/kg) were subcutaneously administered to rats. At 0.5 and 3 hours after λ -carrageenan administration, the edema volume was evaluated using a Plethysmometer. Epinastine hydrochloride significantly suppressed the edema growth in a dose-dependent manner. Cetirizine hydrochloride showed a slight anti-edematous effect, while levocetirizine significantly inhibited the development of edema in a dose-dependent manner. On the other hand, dextrocetirizine did not prevent edema from growing. In summary, second-generation histamine H1 -receptor blockers, at least those examined in this study, may be able to reduce the clinical symptoms of urticaria associated with edema. Levocetirizine hydrochloride is also anticipated to have stronger anti-edematous effects than cetirizine hydrochloride because levocetirizine is responsible for cetirizine\'s anti-edematous activity.
摘要：
荨麻疹是由肥大细胞释放的组胺引起的，肥大细胞会形成风团（水肿）作为视觉特征。在临床实践中,第二代组胺H1受体阻滞剂通常用作荨麻疹的一线对症治疗.然而，没有多少研究直接检测第二代组胺H1受体阻滞剂减轻水肿的能力。在这项研究中,我们直接评估了市场上三种第二代组胺H1受体阻滞剂（盐酸依匹斯汀，盐酸西替利嗪,和盐酸左西替利嗪）使用λ-角叉菜胶诱导的足垫水肿模型。在用1%λ-角叉菜胶注射诱导水肿前一小时，所有第二代组胺H1受体阻滞剂（5、10、50和100mg/kg）均皮下给药至大鼠。在λ-角叉菜胶给药后0.5和3小时，使用体积渗透压计评估水肿体积.盐酸依匹斯汀以剂量依赖性方式显着抑制了水肿的生长。盐酸西替利嗪有轻微的抗水肿作用，而左西替利嗪以剂量依赖性方式显着抑制水肿的发展。另一方面,右西替利嗪不能防止水肿的生长.总之,第二代组胺H1受体阻滞剂，至少在这项研究中检查的那些，可以减轻荨麻疹伴水肿的临床症状。盐酸左西替利嗪还预期比盐酸西替利嗪具有更强的抗水肿作用,因为左西替利嗪负责西替利嗪的抗水肿活性。
