Morgan D A, Anderson E A, Mark A L
Cardiovascular Center, University of Iowa, Iowa City, IA 52242-1081, USA.
Hypertension. 1995 Apr;25(4 Pt 2):834-8. doi: 10.1161/01.hyp.25.4.834.
A low level of sympathetic nerve activity (SNA) to brown adipose tissue has been found in genetically obese Zucker rats and may promote obesity through decreased thermogenesis. In contrast, acquired obesity is reportedly associated with increased SNA. To determine whether low SNA levels in obese Zucker rats extend to the kidney, we compared baseline levels of renal SNA in obese and lean conscious unrestrained Zucker rats fed for 2 weeks on low salt (0.4% NaCl) and high salt (8.0% NaCl) diets. Baseline renal SNA was calculated from multifiber recordings obtained before death under conscious, resting conditions and after death. Body weight averaged 490 +/- 12 g (mean +/- SEM) in obese rats (n = 17) and 339 +/- 7 g in lean rats (n = 19). Mean arterial pressure did not differ in obese and lean Zucker rats fed the low salt diet. However, on the high salt diet, mean arterial pressure was significantly higher in obese rats (n = 8) than in lean rats (n = 9) (113 +/- 3 and 101 +/- 3 mm Hg, respectively; P < .05). Baseline renal SNA was approximately 2 to 2.5 times higher (P < .05) in obese rats than in lean rats in all groups. These studies suggest that obese Zucker rats have heightened levels of SNA to the kidney in contrast to reduced SNA to brown adipose tissue.
在遗传性肥胖的 Zucker 大鼠中，已发现其对棕色脂肪组织的交感神经活动（SNA）水平较低，这可能通过减少产热促进肥胖。相比之下，据报道后天性肥胖与 SNA 增加有关。为了确定肥胖 Zucker 大鼠的低 SNA 水平是否也延伸至肾脏，我们比较了在低盐（0.4% NaCl）和高盐（8.0% NaCl）饮食喂养 2 周的肥胖和瘦的清醒不受约束的 Zucker 大鼠的肾脏 SNA 基线水平。基线肾脏 SNA 是根据在清醒、休息状态下死亡前和死亡后获得的多纤维记录计算得出的。肥胖大鼠（n = 17）的体重平均为 490 +/- 12 g（平均值 +/- 标准误），瘦大鼠（n = 19）的体重平均为 339 +/- 7 g。喂食低盐饮食的肥胖和瘦 Zucker 大鼠的平均动脉压没有差异。然而，在高盐饮食中，肥胖大鼠（n = 8）的平均动脉压显著高于瘦大鼠（n = 9）（分别为 113 +/- 3 和 101 +/- 3 mmHg；P <.05）。在所有组中，肥胖大鼠的基线肾脏 SNA 比瘦大鼠高约 2 至 2.5 倍（P <.05）。这些研究表明，与对棕色脂肪组织的 SNA 降低相反，肥胖 Zucker 大鼠对肾脏的 SNA 水平升高。
