Schobel H P, Heusser K, Schmieder R E, Veelken R, Fischer T, Luft F C
Department of Medicine IV, Nephrology, University of Erlangen-Nürnberg, Erlangen, Germany.
J Am Soc Nephrol. 1998 Sep;9(9):1581-7. doi: 10.1681/ASN.V991581.
The relationship between sympathetic nerve activity and BP in the early stages of essential hypertension remains unclear. To investigate this relationship further, this study measured resting muscle sympathetic nerve activity (MSNA: representing peripheral vasoconstrictor activity), plasma catecholamines, BP, central venous pressure, and heart rate in 20 young (24 +/- 2 SD yr), lean (body mass index, 24.2 +/- 3.0 kg/m2), male subjects with borderline hypertension (BHT) and in 21 male normotensive (NT) control subjects matched for age and body mass index. A cold pressor test was also performed to evaluate sympathetic reflex responsiveness. Resting mean BP and heart rate were significantly higher in the BHT subjects compared with NT subjects (113 +/- 9 versus 89 +/- 9 mmHg; 74 +/- 8 versus 62 +/- 8 bpm; P < 0.0001 each) with no difference in central venous pressure. Resting MSNA levels tended to be lower in the BHT versus the NT group (12 +/- 6 versus 14 +/- 9 bursts/min, P = NS; 16 +/- 8 versus 22 +/- 13 bursts/100 heartbeats, P = 0.05) and did not correlate with either BP or body mass index. Significant positive correlations were found between resting MSNA and plasma norepinephrine levels in both groups (P < 0.05). Hemodynamic and sympathetic nerve responses to the cold pressor test were similar between the BHT and NT subjects. It is concluded that resting MSNA and plasma norepinephrine levels are correlated in young lean NT and BHT men; however, neither of these variables is correlated with BP. Because MSNA was similar in the two groups, the concept that augmented resting MSNA is important in the early developmental phase of essential hypertension must be reevaluated.
原发性高血压早期交感神经活动与血压之间的关系仍不明确。为进一步研究这种关系，本研究测量了20名年轻（24±2标准差岁）、体型偏瘦（体重指数，24.2±3.0kg/m²）、患有临界高血压（BHT）的男性受试者以及21名年龄和体重指数匹配的血压正常（NT）男性对照受试者的静息肌肉交感神经活动（MSNA：代表外周血管收缩活性）、血浆儿茶酚胺、血压、中心静脉压和心率。还进行了冷加压试验以评估交感神经反射反应性。与NT受试者相比，BHT受试者的静息平均血压和心率显著更高（分别为113±9与89±9mmHg；74±8与62±8次/分钟；P均<0.0001），而中心静脉压无差异。BHT组的静息MSNA水平相较于NT组有降低趋势（分别为12±6与14±9次/分钟，P=无统计学意义；16±8与22±13次/100心跳，P=0.05），且与血压或体重指数均无相关性。两组中静息MSNA与血浆去甲肾上腺素水平之间均存在显著正相关（P<0.05）。BHT和NT受试者对冷加压试验的血流动力学和交感神经反应相似。得出的结论是，在年轻体型偏瘦的NT和BHT男性中，静息MSNA与血浆去甲肾上腺素水平相关；然而，这些变量均与血压无关。由于两组的MSNA相似，原发性高血压早期发展阶段静息MSNA增强很重要这一概念必须重新评估。
