Wittner M, di Stefano A, Wangemann P, Nitschke R, Greger R, Bailly C, Amiel C, Roinel N, de Rouffignac C
Département de Biologie/CEA, CEN Saclay, Gif sur Yvette, France.
Pflugers Arch. 1988 Oct;412(5):516-23. doi: 10.1007/BF00582541.
The effect of antidiuretic hormone (arginine vasopressin, AVP) on transepithelial Na+, Cl-, K+, Ca2+ and Mg2+ net transports was investigated in medullary (mTAL) and cortical (cTAL) segments of the thick ascending limb (TAL) of mouse nephron, perfused in vitro. Transepithelial net fluxes (JNa+, JCl-, JK+, JCa2+, JMg2+) were determined by electron probe analysis of the collected tubular fluid. Transepithelial potential difference (PDte) and transepithelial resistance (Rte) were measured simultaneously. cTAL segments were bathed and perfused with isoosmolal, HCO3- containing Ringer solutions, mTAL segments were bathed and perfused with isoosmolal HCO3- free Ringer solutions. In cTAL segments, AVP (10(-10) mol.l-1) significantly increased JMg2+ and JCa2+ from 0.39 +/- 0.08 to 0.58 +/- 0.10 and from 0.86 +/- 0.13 to 1.19 +/- 0.15 pmol.min-1 mm-1 respectively. Neither JNa+ nor JCl-, (JNa+: 213 +/- 30 versus 221 +/- 28 pmol.min-1 mm-1, JCl-: 206 +/- 30 versus 220 +/- 23 pmol.min-1 mm-1) nor PDte (13.4 +/- 1.3 mV versus 14.1 +/- 1.9 mV) or Rte (24.6 +/- 6.5 omega cm2 versus 22.6 +/- 6.4 omega cm2) were significantly changed by AVP. No significant effect of AVP on net K+ transport was observed. In mTAL segments, Mg2+ and Ca2+ net transports were close to zero and AVP (10(-10) mol.l-1) elicited no effect. However NaCl net reabsorption was significantly stimulated by the hormone, JNa+ increased from 107 +/- 33 to 148 +/- 30 and JCl- from 121 +/- 33 to 165 +/- 32 pmol.min-1 mm-1.(ABSTRACT TRUNCATED AT 250 WORDS)
在体外灌注的小鼠肾单位髓质（mTAL）和皮质（cTAL）厚升支（TAL）节段中，研究了抗利尿激素（精氨酸血管加压素，AVP）对跨上皮Na⁺、Cl⁻、K⁺、Ca²⁺和Mg²⁺净转运的影响。通过对收集的肾小管液进行电子探针分析来测定跨上皮净通量（JNa⁺、JCl⁻、JK⁺、JCa²⁺、JMg²⁺）。同时测量跨上皮电位差（PDte）和跨上皮电阻（Rte）。cTAL节段用等渗、含HCO₃⁻的林格溶液进行浴灌流，mTAL节段用等渗无HCO₃⁻的林格溶液进行浴灌流。在cTAL节段中，AVP（10⁻¹⁰ mol·L⁻¹）使JMg²⁺和JCa²⁺分别从0.39±0.08显著增加到0.58±0.10以及从0.86±0.13增加到1.19±0.15 pmol·min⁻¹·mm⁻¹。AVP对JNa⁺、JCl⁻（JNa⁺：213±30对221±28 pmol·min⁻¹·mm⁻¹，JCl⁻：206±30对220±23 pmol·min⁻¹·mm⁻¹）、PDte（13.4±1.3 mV对14.1±1.9 mV）或Rte（24.6±6.5 Ω·cm²对22.6±6.4 Ω·cm²）均无显著影响。未观察到AVP对K⁺净转运有显著作用。在mTAL节段中，Mg²⁺和Ca²⁺净转运接近零，AVP（10⁻¹⁰ mol·L⁻¹）无作用。然而，该激素显著刺激了NaCl的净重吸收，JNa⁺从107±33增加到148±30，JCl⁻从121±33增加到165±32 pmol·min⁻¹·mm⁻¹。（摘要截断于250字）
