Nordt F J, Jack W, Coull B M
Oregon Health Sciences University, Department of Neurology, Portland 97201, USA.
J Cardiovasc Pharmacol. 1990;16 Suppl 3:S29-32.
Erythrocyte aggregation is an important determinant of the rheological behavior of blood and may play a critical role in nutritive tissue perfusion at the level of the microcirculation, particularly in situations of low flow. Thus, abnormal red blood cell aggregation may contribute to the pathophysiology of a variety of vascular diseases with associated microcirculatory disturbances. The action of serotonergic antagonists has a hemorheological component, although red blood cell aggregation specifically has not been addressed previously. Therefore, the effect of naftidrofuryl, a 5-hydroxytryptamine-2 receptor antagonist (5-HT2), on erythrocyte aggregation was studied in whole blood obtained from adult human volunteers. Red blood cell aggregation was measured using a Myrenne aggregometer the operation of which is based on nephelometric principles. The results demonstrate that red blood cell aggregation is significantly reduced in comparison to controls on incubation of whole blood in the presence of naftidrofuryl. This inhibitory effect is concentration dependent and reaches a maximum (approximately 30%) between 1 and 10 microM naftidrofuryl. Furthermore, naftidrofuryl (5 microM) also inhibits red blood cell aggregation in the presence of exogenously added serotonin (1 microM) on average by approximately 18%. Significant inhibition of red blood cell aggregation could not be observed in similar experiments using whole blood suspensions essentially devoid of platelets, suggesting that these blood cellular elements are involved in mediating the effects of naftidrofuryl.
红细胞聚集是血液流变学行为的一个重要决定因素，可能在微循环水平的营养组织灌注中起关键作用，尤其是在低流量情况下。因此，异常的红细胞聚集可能导致各种伴有微循环障碍的血管疾病的病理生理过程。血清素能拮抗剂的作用具有血液流变学成分，尽管红细胞聚集这一特定方面此前尚未得到研究。因此，我们研究了5-羟色胺-2受体拮抗剂（5-HT2）萘呋胺酯对从成年人类志愿者获取的全血中红细胞聚集的影响。使用基于比浊法原理操作的Myrenne血细胞聚集仪测量红细胞聚集。结果表明，在萘呋胺酯存在的情况下对全血进行孵育时，与对照组相比，红细胞聚集显著降低。这种抑制作用呈浓度依赖性，在萘呋胺酯浓度为1至10微摩尔时达到最大值（约30%）。此外，在存在外源性添加的血清素（1微摩尔）的情况下，萘呋胺酯（5微摩尔）平均也能抑制红细胞聚集约18%。在使用基本不含血小板的全血悬浮液进行的类似实验中未观察到对红细胞聚集的显著抑制，这表明这些血细胞成分参与介导萘呋胺酯的作用。
