Nilsson H, Ely D, Friberg P, Karlström G, Folkow B
Acta Physiol Scand. 1985 Oct;125(2):323-34. doi: 10.1111/j.1748-1716.1985.tb07722.x.
As part of our studies in normotensive (WKY) and hypertensive (SHR) rats concerning the cardiovascular effects of 240-fold variations in sodium (Na) intake, the present experiments explore how vascular design, smooth-muscle sensitivity to noradrenaline and adrenergic vasoconstrictor fibre function are affected. In vitro comparisons were performed on pair-perfused hindquarter vascular beds and on paired small mesenteric arteries (diameter 150-200 micron), using a two-vessel Mulvany-Halpern myograph. Preparations were taken from WKY and SHR which between 5 and 12-13 weeks of age were on 'low' (LNa, 0.5), 'control' (CNa, 5), 'high' (HNa, 50) or 'very high' (vHNa, 120 mmol Na 100 g-1 food) sodium diets. Structural vascular adaptation occurred only when arterial pressure was altered (only in LNa SHR). In both preparations smooth-muscle sensitivity and dose-response curves to noradrenaline remained unaffected by the Na diets. However, in both LNa groups the frequency-response curves to vasoconstrictor fibre stimulation in the small arteries were displaced to the right of the CNa one, with generally attenuated responses, while the curves of particularly the vHNa arteries were displaced to the left, with enhanced responses. Inhibition of NaKATPase by ouabain particularly enhanced the neurogenic responses, but to similar extents in all Na groups. Thus, low sodium intake apparently reduces the transmitter release/impulse in adrenergic neurons, while it increases the transmitter stores. High sodium intake has the opposite effects. These adaptations of adrenergic neuronal function may be one of the most important long-term consequences of altered sodium intake.
作为我们对正常血压（WKY）和高血压（SHR）大鼠进行的关于钠（Na）摄入量240倍变化对心血管影响研究的一部分，本实验探讨了血管设计、平滑肌对去甲肾上腺素的敏感性以及肾上腺素能血管收缩纤维功能是如何受到影响的。使用双血管Mulvany - Halpern肌动描记器，对成对灌注的后肢血管床和成对的小肠系膜动脉（直径150 - 200微米）进行了体外比较。制备物取自5至12 - 13周龄的WKY和SHR大鼠，它们分别处于“低”（LNa，0.5）、“对照”（CNa，5）、“高”（HNa，50）或“非常高”（vHNa，120 mmol Na 100 g⁻¹食物）钠饮食状态。仅当动脉血压改变时（仅在LNa SHR中）才出现血管结构适应性变化。在两种制备物中，平滑肌对去甲肾上腺素的敏感性和剂量反应曲线均不受钠饮食的影响。然而，在两个LNa组中，小动脉对血管收缩纤维刺激的频率反应曲线都向右偏移至CNa组曲线的右侧，反应普遍减弱，而特别是vHNa动脉的曲线向左偏移，反应增强。哇巴因抑制钠钾ATP酶特别增强了神经源性反应，但在所有钠组中增强程度相似。因此，低钠摄入明显减少了肾上腺素能神经元中的递质释放/冲动，同时增加了递质储存。高钠摄入则有相反的作用。肾上腺素能神经元功能的这些适应性变化可能是钠摄入量改变最重要的长期后果之一。
