饮食中钠摄入量对未麻醉大鼠血压及对血管紧张素II心输出量反应的影响。

The effect of dietary sodium intake on the blood pressure and cardiac output responses to angiotensin II in unanaesthetized rats.

Slack B L, Ledingham J M

Clin Sci Mol Med. 1977 Jun;52(6):571-6. doi: 10.1042/cs0520571.

Abstract

Dose-response curves for the pressor activity of angiotensin II have been determined in unanaesthetized rats receiving diets containing 2-5% (w/w) or 0-007% (w/w) sodium and administered in various sequences. 2. Dose-response curves were shifted to the left in rats on a high-, compared with a low-, sodium intake. This response was maintained for 7 days on changing from high to low sodium. 3. There was no difference in the relation between the fall of cardiac output and the rise of blood pressure in any of the experimental groups. 4. Dose-response curves for peripheral resistance showed the same directional change as seen for the pressor response in rats on high- and low-sodium diets. Since depression of cardiac output was proportional to the pressure rise, the absolute change in peripheral resistance was greater than the blood pressure response. The proportional changes were similar. 5. It is concluded that alterations in the pressor response to angiotensin caused by changes in sodium loading are attributable to changes in peripheral resistance and not to changes in the cardiac output response to the acute rise in blood pressure.

摘要

已在摄入含2 - 5%（w/w）或0.007%（w/w）钠的饲料且未麻醉的大鼠中，以不同顺序给药，测定了血管紧张素II升压活性的剂量 - 反应曲线。2. 与低钠摄入的大鼠相比，高钠摄入大鼠的剂量 - 反应曲线向左移动。从高钠改为低钠后，这种反应持续7天。3. 在任何实验组中，心输出量下降与血压升高之间的关系均无差异。4. 外周阻力的剂量 - 反应曲线显示出与高钠和低钠饮食大鼠的升压反应相同的方向变化。由于心输出量的降低与血压升高成比例，外周阻力的绝对变化大于血压反应。比例变化相似。5. 得出的结论是，钠负荷变化引起的对血管紧张素升压反应的改变归因于外周阻力的变化，而非心输出量对血压急性升高的反应变化。