Yamanaka S, Miura K, Yukimura T, Yamamoto K
Department of Pharmacology, Osaka City University Medical School, Japan.
Prostaglandins. 1993 Mar;45(3):221-8. doi: 10.1016/0090-6980(93)90048-c.
Plasma concentration of 11-dehydro thromboxane B2 (TxB2) is reported to be a reliable indicator of TxA2 production in human and rabbit. The purpose of this study is to examine whether we can use this parameter in dogs. The plasma concentration of 11-dehydro TxB2 was determined by enzyme immunoassay method using anti-11-dehydro TxB2 monoclonal antibody. When 10 micrograms/kg of TxB2 was intravenously administered to dogs in which endogenous production of prostanoids was blocked by aspirin, the plasma concentrations of 11-dehydro TxB2 before and 2, 5, 15, 60 min after TxB2 administration were 6.2 +/- 1.4, 54.2 +/- 5.0, 65.2 +/- 14.3, 65.2 +/- 16.4 and 31.0 +/- 7.5 pg/ml, while the corresponding TxB2 levels were 20.1 +/- 3.1, 3143.3 +/- 379.5, 1432.6 +/- 120.5, 356.8 +/- 38.9, and 128.9 +/- 13.6 pg/ml, respectively. Platelet-activating factor (PAF, 0.5 micrograms/kg) induced pulmonary vasoconstriction which was blocked by aspirin and OKY-046 (TxA2 synthetase inhibitor), indicating that TxA2 mediated this change. Plasma concentration of 11-dehydro TxB2 was increased by PAF. This change was also blocked by aspirin and OKY-046. These data suggest that the determination of plasma concentration of 11-dehydro TxB2 is useful to estimate the in vivo production of TxA2 in dogs.
据报道，11-脱氢血栓素B2（TxB2）的血浆浓度是人和兔体内血栓素A2（TxA2）生成的可靠指标。本研究的目的是检验我们是否可以在犬类中使用该参数。采用抗11-脱氢TxB2单克隆抗体的酶免疫分析法测定11-脱氢TxB2的血浆浓度。当向用阿司匹林阻断前列腺素内源性生成的犬静脉注射10微克/千克的TxB2时，注射TxB2前以及注射后2、5、15、60分钟时11-脱氢TxB2的血浆浓度分别为6.2±1.4、54.2±5.0、65.2±14.3、65.2±16.4和31.0±7.5皮克/毫升，而相应的TxB2水平分别为20.1±3.1、3143.3±379.5、1432.6±120.5、356.8±38.9和128.9±13.6皮克/毫升。血小板活化因子（PAF，0.5微克/千克）诱导肺血管收缩，这被阿司匹林和OKY-046（TxA2合成酶抑制剂）阻断，表明TxA2介导了这一变化。PAF使11-脱氢TxB2的血浆浓度升高。这一变化也被阿司匹林和OKY-046阻断。这些数据表明，测定11-脱氢TxB2的血浆浓度有助于评估犬体内TxA2的生成情况。
