Rübsamen K, von Engelhardt W
Pflugers Arch. 1981 Aug;391(2):141-6. doi: 10.1007/BF00657005.
The interrelationship between the absorption of Na, H ions and short chain fatty acids (SCFA) and the secretion of HCO3 in the sheep colon was studied using an in vivo perfusion technique. 1. Under control conditions net SCFA absorption was 62.9 +/- 6.1 mmol . h-1, net Na absorption 49.8 +/- 7.6 mmol . h-1. HCO3 accumulated in the colon lumen at a rate of 5.1 +/- 2.9 mmol . h-1. 2. When 30, 50, or 70% of the Na in the perfusion solution were replaced by Li, Na transport was gradually inhibited and even abolished when 70 mmol . 1(-1) of Li were present. SCFA absorption also decreased, however, to a lower degree. 3. Net Na transport was higher in the presence than in the absence of SCFA. This difference disappeared when Na transport was inhibited by Li. 4. HCO3 accumulation in the colon lumen significantly increased with increasing Li concentrations up to a maximum of 21.7 +/- 7.1 mmol . h-1 when 50% of Na were replaced by Li, however, only in the presence of SCFA. 5. Neither increasing Li concentrations nor the presence or absence of SCFA influenced the H ion disappeared from the perfusion solution. 6. These results indicate that net absorption of Na and SCFA in sheep colon are closely linked to the availability of H ions.
采用体内灌注技术研究了绵羊结肠中钠、氢离子和短链脂肪酸（SCFA）的吸收与碳酸氢根分泌之间的相互关系。1. 在对照条件下，SCFA的净吸收量为62.9±6.1 mmol·h⁻¹，钠的净吸收量为49.8±7.6 mmol·h⁻¹。碳酸氢根以5.1±2.9 mmol·h⁻¹的速率在结肠腔内蓄积。2. 当灌注液中30%、50%或70%的钠被锂取代时，钠转运逐渐受到抑制，当存在70 mmol·L⁻¹的锂时甚至被消除。SCFA的吸收也降低了，但程度较低。3. 存在SCFA时的钠净转运高于不存在SCFA时。当钠转运被锂抑制时，这种差异消失。4. 随着锂浓度的增加，结肠腔内碳酸氢根的蓄积显著增加，当50%的钠被锂取代时，最高可达21.7±7.1 mmol·h⁻¹，但仅在存在SCFA的情况下。5. 锂浓度的增加以及SCFA的存在与否均不影响灌注液中氢离子的消失。6. 这些结果表明，绵羊结肠中钠和SCFA的净吸收与氢离子的可利用性密切相关。
