Damas J, Remacle-Volon G, Bourdon V
Université de Liège, Belgium.
Eur J Pharmacol. 1993 Feb 9;231(2):231-6. doi: 10.1016/0014-2999(93)90454-p.
Platelet-activating factor (PAF; 2.5 micrograms/kg) injected in the tail vein of anaesthetized rats increased the vascular permeability of the duodenum, paws, skin and muscles, as measured by the extravasation of 125I-labelled albumin. It did not affect the permeability of the lungs or the presence of labelled albumin in the liver and spleen. The effects of PAF were dose dependently inhibited by WEB 2086 (ID50: 1.39 to 2.09 mg/kg) and SM-12502 (ID50: 7.17 to 8.36 mg/kg). Zymosan, an activator of the alternative complement pathway (10 or 16 mg/kg), induced protein extravasation in the lungs, duodenum, paws and skin, and the accumulation of labelled albumin in the liver. The effects of zymosan on the duodenum and liver were dose dependently inhibited by WEB-2086 and SM-12502. Both PAF antagonists increased the effects of zymosan in the paws but they did not affect protein extravasation in the lungs. The hypotensive effect of PAF (0.5 micrograms/kg) was inhibited by WEB 2086 (ID50: 1.21 mg/kg) and SM-12502 (ID50: 13.4 mg/kg). Both PAF antagonists reduced the hypotensive effects of zymosan (4 or 16 mg/kg) with a similar relative inhibitory potency. PAF is the major mediator involved in the hypotensive effect of zymosan but plays only a minor role in the permeability-enhancing effect of zymosan, mostly in the splanchnic area.
通过尾静脉向麻醉大鼠注射血小板激活因子（PAF；2.5微克/千克），会增加十二指肠、爪子、皮肤和肌肉的血管通透性，这是通过125I标记白蛋白的外渗来测量的。它不会影响肺部的通透性，也不会影响肝脏和脾脏中标记白蛋白的存在。PAF的作用被WEB 2086（半数抑制剂量：1.39至2.09毫克/千克）和SM - 12502（半数抑制剂量：7.17至8.36毫克/千克）剂量依赖性地抑制。酵母聚糖是替代补体途径的激活剂（10或16毫克/千克），可诱导肺部、十二指肠、爪子和皮肤中的蛋白质外渗，以及肝脏中标记白蛋白的积累。酵母聚糖对十二指肠和肝脏的作用被WEB - 2086和SM - 12502剂量依赖性地抑制。两种PAF拮抗剂均增加了酵母聚糖对爪子的作用，但不影响肺部的蛋白质外渗。PAF（0.5微克/千克）的降压作用被WEB 2086（半数抑制剂量：1.21毫克/千克）和SM - 12502（半数抑制剂量：13.4毫克/千克）抑制。两种PAF拮抗剂均以相似的相对抑制效力降低了酵母聚糖（4或16毫克/千克）的降压作用。PAF是参与酵母聚糖降压作用的主要介质，但在酵母聚糖的通透性增强作用中仅起次要作用，主要在内脏区域。
