Assessment of the central and peripheral alpha_2-adrenoceptor activities by using the platelet in inflammation.

使用炎症中的血小板评估中枢和外周 α_2-肾上腺素受体活性。

• 批准号: 07660427
• 负责人: HIKASA Yoshiaki
• 金额: $ 1.47万
• 依托单位: Kitasato University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1996
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07660427/
• 关键词: Inflammation; Platelet; Central nervous system; Peripheral system; alpha_2-adrenoceptor

The purpose of this study was to investigate the relationship between the platelet alpha_2-adrenoceptor activity and the central and peripheral alpha_2-adrenoceptor activities in inflammable dogs. For this purpose, the aggregatory an anti-aggregatory effects of various imidazoline or non-imidazoline alpha-adrenergic agents on canine blood platelets werer examined. Then, we examined the changes in alpha_2-adrenoceptor binding on platelet and brain membranes, and the alpha_2-adrenoceptor mediated various effects in dogs that were inflamed acutely and chronically. This study showed that imidazoline alpha-adrenergic agents and/or alpha_2-adrenoceptor blocking agents inhibit effectively the epinephrine-potentiated platelet aggregation in dogs. Therefore, it is conceivable that epinephrine-potentiated platelet aggregation in dogs is mediated by alpha_2-adrenoceptors. However, imidazoline receptors as non-adrenergic binding sites may exist on canine blood platelet. Acute inflammation induced … More by a non-lethal endotoxin injection decreased Bmax of [^3H] yohimbine binding and increased Kd in platelets, whereas in either cerebral cortex or medulla oblongata, both Bmax and Kd decreased. Pretreatment with endotoxin diminished cardiovascular effects such as bradycardia, hypotention, and increase in systemic vascular resistance induced by alpha_2-adrenoceptor agonists. Chronic arthritis induced by weekly intra-articular injection of carrageenin decreased Bmax of [^3H] yohimbine binding in platelets, and decreased Kd in either cerebral cortex or medulla oblongata. This chronic inflammation reduced the sedation, bradycardia and other effects induced by alpha_2-adrenoceptor agonists, and the effect of yohimbine in inhibiting the epinephrine-potentiatedplatelet aggregation. These results suggest that alpha_2-adrenoceptor activity is impaired in the central nervous system as well as peripheral system during acute and chronic inflammations. Therefore, platelets may in part have a significance for diagnosis of alpha_2-adrenoceptor changes in the central nervous system or peripheral system in inflamed dogs. Less

本研究的目的是研究易燃犬血小板α2-肾上腺素受体活性与中枢和外周α2-肾上腺素受体活性之间的关系，为此目的，研究各种咪唑啉或非咪唑啉α-肾上腺素受体的聚集和抗聚集作用。然后，我们检查了犬血小板上的肾上腺素能药物对血小板和大脑的α2-肾上腺素受体结合的变化。该研究表明，咪唑啉α肾上腺素能药物和/或α2肾上腺素受体阻滞剂可有效抑制狗体内肾上腺素增强的血小板聚集。可以想象，狗体内肾上腺素增强的血小板聚集是由然而，咪唑啉受体作为非肾上腺素能结合位点可能存在于犬血小板上，由非致死性内毒素注射 [^3H] 育亨宾结合和 Kd 增加引起的急性炎症，而在任何一种情况下。大脑皮层或延髓，Bmax 和 Kd 均降低，内毒素预处理可减少心血管效应，如心动过缓、低血压和心律失常。 α_2-肾上腺素受体激动剂引起的全身血管阻力增加。每周关节内注射角叉菜胶引起的慢性关节炎降低了血小板中[^3H]育亨宾结合的Bmax，并降低了大脑皮质或延髓中的Kd。这种慢性炎症减少了。 α_2-肾上腺素受体激动剂引起的镇静、心动过缓等作用以及育亨宾的抑制作用这些结果表明，在急性和慢性炎症期间，中枢神经系统和外周系统中的α2-肾上腺素受体活性受损，因此，血小板可能对诊断α2-肾上腺素受体变化具有一定意义。发炎狗的中枢神经系统或外周系统较少。