大鼠心脏和冠状血管多巴胺D2受体的年龄相关变化。
文章的细节
-
引用
复制到剪贴板 -
卡瓦洛蒂C, Nuti F, Bruzzone P, Mancone M
大鼠心脏和冠状血管多巴胺D2受体的年龄相关变化。
临床经验与药理。2002 May-Jun;29(5-6):412-8。
- PubMed ID
-
12010185 (PubMed视图］
- 摘要
-
1.研究了多巴胺D2受体在大鼠心脏和冠状血管中的分布，以及D2受体密度可能与年龄相关的变化。应用联合结合技术和光显微自显影技术研究了大鼠心脏和冠状血管中多巴胺d2样受体位点的药理特征和解剖位置。2.从年轻和年老的大鼠身上采集心脏和冠状血管样本。在冷冻切片上，多巴胺能D2受体通过选择性D2配体标记，即[3H]-螺哌酮(螺哌酮)。使用未标记激动剂和/或标记和未标记拮抗剂进行抑制研究，以确定结合的药理学特异性。生理实验证实了D2受体与多种多巴胺能药物的选择性拮抗作用。3.[3H]-螺哌啶醇与大鼠心脏和冠状动脉部分结合(与多巴胺d2样受体的标记方式一致)，其平衡解离常数约为2.4 +/- 0.7 nmol/L，最大结合位点容量为65.8 +/- 4.5 fmol/mg蛋白。 Experiments performed on sections of coronary veins did not allow the evaluation of specific binding. Autoradiography, observed with light microscopy, showed the development of specific silver grains within the whole wall of rat heart and coronary artery. The greater sensitivity to displacement by amisulpride, bromocriptine, domperidone, haloperidol, raclopride and L-sulpiride than to displacement by N-propyl-norapomorphine, quinpirole and clozapine suggests that the binding sites observed in these experiments are likely to belong to the dopamine D2 receptor subtype. 4. Comparing results in young and old rats, we observed numerous significant age-related changes, including a decrease in D2 receptors localized in rat heart and coronary artery wall. These D2 receptors show a specific location, in close relationship with dopaminergic nerve fibres. They decrease with age and their role remains unknown.