Wimberger P, Marin-Grez M
University of Munich, Institute of Physiology, Germany.
Kidney Int Suppl. 1998 Sep;67:S180-2. doi: 10.1046/j.1523-1755.1998.06740.x.
The effect of changing extracellular pH (pHo) on intracellular pH (pHi) in mesenteric arterioles of spontaneously hypertensive (SHR) and Wistar-Kyoto (WKY) rats was investigated using the fluorescent indicator seminaphthorhodafluor c-SNARF-1 to measure pHi. Although the pHi of arterioles from WKY varied directly with pHo, that of SHR arterioles varied inversely. This abnormal pHi regulation in SHR was corrected by 50-microM 5-(N-ethylisopropyl)amiloride (EIPA). Vmax of H+ transport in response to changing extracellular Na+ was higher in SHR than in WKY, but Km did not differ. The Hill coefficient for H+ transport with respect to pH; was 1.69 in prehypertensive and 1.56 in hypertensive SHR. These results indicate that the Na+/H+ exchanger is particularly hyperactive in mesenteric arterioles of SHR.
利用荧光指示剂半萘罗丹氟c-SNARF-1测量细胞内pH（pHi），研究了细胞外pH（pHo）变化对自发性高血压大鼠（SHR）和Wistar-Kyoto大鼠（WKY）肠系膜小动脉pHi的影响。虽然WKY小动脉的pHi与pHo呈直接变化关系，但SHR小动脉的pHi却呈相反变化。50微摩尔的5-（N-乙基异丙基）氨氯吡脒（EIPA）纠正了SHR中这种异常的pHi调节。SHR中响应细胞外Na+变化的H+转运的Vmax高于WKY，但Km没有差异。高血压前期SHR中H+转运相对于pH的希尔系数为1.69，高血压SHR中为1.56。这些结果表明，Na+/H+交换体在SHR肠系膜小动脉中特别活跃。
