RACIAL DIFFERENCES IN EXTRARENAL POTASSIUM METABOLISM

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来源获得主要资金， 因此可以在其他CRISP条目中表示。列出的机构是 中心，不一定是研究者的机构。 本研究的主要目的是阐明肾外钾代谢种族差异的病因。 在最近的一项研究中，我们证明了非洲裔美国人在静脉输注后的血清K+水平往往高于白人。 据推测，这是由于在非裔美国人中缓慢的Na+K+ ATP酶泵活性，这被认为是由来自丰富的褪黑激素前体的非神经元多巴胺介导的。 我们以前对卡比多巴（一种非特异性多巴胺合成抑制剂）的研究未能证明这一点，可能是因为它的非特异性阻断。 出于这个原因，我们现在开始使用多巴胺受体拮抗剂甲氧普胺进行研究，并将其与卡比多巴和安慰剂进行比较，看看这种种族差异是否被消除。

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. The primary objective of this study is to elucidate the etiology of racial differences in extrarenal potassium metabolism. In a recent study, we demonstrated that African Americans tend to have higher serum K+ levels after an IV infusion than do Caucasians. It has been postulated that this is due to sluggish Na+K+ ATPase pump activity in African Americans This is thought to be mediated by non-neuronal dopamine from abundant melatonin precursors. Our previous study with carbidopa - a non-specific dopamine synthesis inhibitor, failed to show this, possibly because of its non-specific blockage. For this reason we are now to embark on a study using a dopamine receptor antagonist, metochlopramide, and compare this to carbidopa and placebo to see if this racial difference is obliterated.