Laboratory of Veterinary Parasitology, College of Veterinary Medicine and Bio-safety Research Center, Jeonbuk National University, Specialized Campus, Iksan 54596, Korea.
Department of Medicine Surgery & Obstetrics, Faculty of Veterinary and Animal Science, Hajee Mohammad Danesh Science and Technology University, Dinajpur-5200, Bangladesh.
Parasites Hosts Dis. 2023 May;61(2):172-182. doi: 10.3347/PHD.22068. Epub 2023 May 23.
At the time of host attachment, ticks are very sensitive to histamine, but during rapid blood sucking they paradoxically require histamine. Using a rabbit model, we studied the effects of histamine and antihistamine during attachment and fast-feeding in different life stages of Haemaphysalis longicorns. We examined how they responded to histamine and antihistamine by analyzing the detachment rate, histology of feeding lesions, and post-feeding behavior. A significant difference (P<0.01) was found in the detachment rate between experimental and control treatments throughout the observation period. Ticks exhibited a higher detachment rate (30.1%) at 12 h after histamine application during attachment time and on antihistamine-treated skin (25.4%) at 96 h during fast-feeding. After feeding on histamine-treated rabbits, the fully engorged body weights of larvae and nymphs were 0.7±0.36 mg and 3.5±0.65 mg, respectively. An average increase in body weight of 0.6±0.05 mg and 3.2±0.30 mg was observed for larvae and nymphs compared to the respective control weights. Nymphs and adults engorged after antihistamine treatment had an average body weight of 1.3±0.54 mg and 54±0.81 mg, respectively. An average decrease in body weight was observed in antihistamine-treated H. longicornis compared with control nymphs (3.3±0.42 mg) and adults (174±1.78 mg). Skin biopsies were collected after treatment, and differential histopathological characteristics were found between the treatment and control groups. Tick-infested skin collected from rabbits in the antihistamine-treated group lacked erythrocytes in the feeding pool, indicating that antihistamine impaired tick fast-feeding stage.
在宿主附着时，蜱虫对组氨酸非常敏感，但在快速吸血时却反常地需要组氨酸。我们使用兔模型研究了组氨酸和抗组氨酸在长角血蜱不同生活阶段附着和快速进食过程中的作用。我们通过分析脱离率、进食损伤的组织学和进食后行为来研究它们对组氨酸和抗组氨酸的反应。在整个观察期间，实验组和对照组之间的脱离率存在显著差异（P<0.01）。在附着时间内，应用组氨酸后 12 小时，蜱虫的脱离率更高（30.1%），而在快速进食期间，抗组氨酸处理的皮肤的脱离率更高（25.4%）。在给用组氨酸处理过的兔子喂食后，幼虫和若虫的完全饱血体重分别为 0.7±0.36mg 和 3.5±0.65mg。与各自的对照体重相比，幼虫和若虫的体重平均增加了 0.6±0.05mg 和 3.2±0.30mg。抗组氨酸处理后，若虫和成虫的饱血体重平均为 1.3±0.54mg 和 54±0.81mg。与对照若虫（3.3±0.42mg）和成虫（174±1.78mg）相比，抗组氨酸处理的长角血蜱的体重平均减轻。治疗后采集皮肤活检，发现治疗组和对照组之间存在差异的组织病理学特征。从抗组氨酸处理组的兔子身上采集的带蜱皮肤，进食池内缺乏红细胞，表明抗组氨酸损害了蜱的快速进食阶段。
