ST JOHN'S WORT AND PLATELET ANTI-AGGREGATORY EFFECT OF CLOPIDOGREL

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 这项研究的目的是确定是否草药治疗称为圣约翰草是有效的，在提高活性的药物称为氯吡格雷（出售的名称为Plavidine）。血小板抑制血小板功能，就像阿司匹林一样。 血小板是血液中的微小细胞，聚集在一起止血。 这种聚集被称为聚集，这是正常血小板所做的。 当一个人服用Plastine时，它会停止血小板的作用，因此被称为抗血小板药物。 圣约翰草（不受FDA监管）是治疗抑郁症的替代疗法。 许多药物，包括圣约翰麦芽汁和血小板，通过肝脏，需要一种叫做CYP 3A 4的酶才能代谢，这样身体就可以利用它们来达到预期的目的。 现在已知圣约翰草刺激这种肝酶CYP 3A 4的产生。 因此，在服用血小板减少素与圣约翰草联合治疗的患者中，我们将预期看到血小板减少素对血小板的作用增加。 在最近的一项研究中，我们发现并不是所有的患者都以相同的方式对血小板产生反应。换句话说，在某些患者中，它比其他患者更有效。 对血小板的反应是通过测量血小板功能百分比的血液测试来确定的，血小板功能百分比是口服血小板后保持功能的总血小板的百分比。 对血小板减少有反应者在血小板减少后将具有e70%的血小板活性抑制，低反应者将具有<70%的血小板减少抑制反应。 除了测量血小板功能，我们有兴趣知道，当服用圣约翰草时，这种肝酶CYP 3A 4的活性是否实际上以可测量的量增加。 将使用红霉素呼气试验（ERMBT）测量CYP 3A 4的活性。 本研究将招募100名年龄在18-60岁之间的健康志愿者成年男性和女性受试者，不限人种或种族。 被确定为Plastine应答者的受试者将从研究中排除。 被确定为对Plastine的低-低应答者的受试者将被纳入研究。 本研究的主要目的是观察圣约翰草与血小板减少剂联合使用是否会增加血小板减少剂的抗血小板作用。 我们还想确定圣约翰麦芽汁是否以可测量的量增强肝酶CYP 3A 4，并将使用ERMBT进行测量。 第二个目的是，根据这些发现，我们可以向医生推荐对Plastine无反应的患者的潜在替代治疗。'

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. This study is designed to determine whether the herbal therapy called St. John's wort is effective in enhancing the activity of a drug called clopidogrel (sold under the name Plavix). Plavix inhibits platelet function, much like aspirin. Platelets are tiny cells in your blood stream that clump together to stop bleeding. This clumping is called aggregation and is what normal platelets do. When a person takes Plavix it stops the action of the platelet and thus is called an antiplatelet drug. St. John's wort (not FDA-regulated) is given as an alternative therapy to treat depression. Many medications that are taken, including St. John's wort and Plavix, pass through the liver and require an enzyme called CYP3A4 in order to be metabolized so that the body can use them for the purpose for which they were intended. It is now known that St. John's wort stimulates the production of this liver enzyme CYP3A4. It follows then, that in patients who take Plavix in combination with St. John's wort, we will expect to see an increase effect of Plavix on the platelets. In a recent study we found that not all patients respond to Plavix in the same way. In other words, in some patients it was more effective than in others. The response to Plavix is determined by a blood test that measures percent platelet function, which is the percent of the total platelets that remains functional after Plavix is given orally by mouth. Responders to Plavix will have e70% inhibition of platelet activity post Plavix and low-responders will have <70% platelet inhibitory response to Plavix. In addition to measuring platelet function, we are interested in knowing if, when taking St.John's wort, the activity of this liver enzyme CYP3A4 is actually increased in a measurable amount. Measuring the activity of CYP3A4 will be done with the Erythromycin Breath Test (ERMBT). This study will recruit 100 healthy volunteer adult male and female subjects of any race or ethnicity, aged 18-60. The subjects, who are determined to be responders to Plavix, will be excluded from the study. The subjects who are determined to be low-low responders to Plavix will be included in the study. The primary purpose of the study is to see whether St. John's wort when used in combination with Plavix will increase the antiplatelet action of Plavix. We also want to determine if St. John's wort enhances the liver enzyme CYP3A4 in a measurable amount and will use the ERMBT for that measurement. The secondary purpose is that with these findings, we may be able to make recommendations to physicians on a potential alternative treatment for those patients who do not respond to Plavix.'