Plasma renin activity is significantly lower in black people compared with whites independent of age and blood pressure status. The lower PRA appears to be due to a reduction in the rate of secretion of renin but the exact mechanistic events underlying such differences in renin release between blacks and whites are still not fully understood. Nevertheless, given the paramount importance of the renin-angiotensin system in the control of sodium balance, a most likely explanation is that the lower renin is a consequence of differences in renal sodium handling between blacks and whites. The lower PRA does not reflect differences in dietary sodium intake but the evidence available suggests that the low PRA could be part of the corrective mechanisms designed to maintain sodium balance in the presence of an increased tendency for sodium retention in black people. While it is possible that several factors may contribute to the reduced PRA, more recent investigation at the molecular level suggests that the lower PRA may arise from gene variation in the renal epithelial sodium channel. The functional significance of the lower PRA in relation to the different pattern of cardiovascular and renal disease between blacks and whites remains unclear. Moreover, direct investigations of pre-treatment renin status in hypertensive blacks in relation to blood pressure response have demonstrated that the pre-treatment PRA is not a good index of subsequent blood pressure response to pharmacological treatment. Nevertheless, the blood pressure reduction to short term sodium restriction is greater in blacks compared with whites and, in the black subjects, the greater reduction in blood pressure to sodium restriction appears to be related, at least in part, to the decreased responsiveness of the renin-angiotensin system. Journal of Human Hypertension (2001) 15, 17-25

中文翻译：

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为什么非洲裔人群血浆肾素活性降低？

与白人相比，与年龄和血压状况无关，血浆中的血浆肾素活性明显低于白人。较低的PRA似乎是由于肾素分泌速率降低所致，但仍未完全了解黑人和白人之间肾素释放差异的确切机制。尽管如此，鉴于肾素-血管紧张素系统在控制钠平衡中的重要性，最有可能的解释是，较低的肾素是黑人和白人之间肾钠处理差异的结果。较低的PRA不能反映出饮食中钠的摄入量的差异，但是现有证据表明，较低的PRA可能是纠正机制的一部分，该机制旨在在黑人体内钠retention留趋势增加的情况下保持钠平衡。虽然可能有几种因素可能导致PRA降低，但在分子水平上的最新研究表明，较低的PRA可能源自肾上皮钠通道的基因变异。较低的PRA与黑人和白人之间心血管疾病和肾脏疾病的不同模式有关的功能意义尚不清楚。此外，对高血压黑人中治疗前肾素状态与血压反应的直接研究表明，治疗前PRA并不是药物治疗后血压反应的良好指标。然而，黑人与白人相比，血压降低至短期钠限制的幅度更大，而在黑人受试者中，血压对钠限制的降低幅度更大，至少部分地与高血压的反应性有关。肾素-血管紧张素系统。人类高血压杂志（2001）15，17-25 血压对钠限制的更大降低似乎至少部分与肾素-血管紧张素系统的反应性降低有关。人类高血压杂志（2001）15，17-25 血压对钠限制的更大降低似乎至少部分与肾素-血管紧张素系统的反应性降低有关。人类高血压杂志（2001）15，17-25