Zicha J, Duhm J
Institute of Physiology, University of Munich, Germany.
Hypertension. 1990 Jun;15(6 Pt 1):612-27. doi: 10.1161/01.hyp.15.6.612.
Blood pressure response to chronic high salt intake and kinetics of red blood cell Na+ and K+ (Rb+) transport were studied in salt-sensitive (DS) and salt-resistant (DR) Dahl rats fed a high salt diet (8% NaCl) for 7 weeks from the fifth (young), 12th (adult), or 23rd (old) week of age. The kinetics of ouabain-sensitive Rb+ uptake and Na+ extrusion were determined in Na+ media as a function of both intracellular Na+ (Na+i, 2-8 mmol/l cells) and extracellular Rb+ (Rb+o). In addition, the kinetics of furosemide-sensitive Rb+ uptake (related to Rb+o) and the magnitude of the Na+ and Rb+ leaks were assessed. High salt induced hypertension in young and adult but not in old DS rats although red blood cell Na+ was slightly increased in all age groups of DS rats fed a high salt diet. The kinetic parameters of the Na(+)-K+ pump were similar in DS and DR rats fed a low salt diet. Ouabain-sensitive transport rates were not suppressed in erythrocytes of salt hypertensive Dahl rats. Maximal velocities of the Na(+)-K+ pump (related to Na+i) decreased significantly with age in all groups except in DS rats fed a high salt diet. This was compensated by an age-dependent increase in the affinity for Na+i so that no substantial differences in transport rates between young and old rats were seen at physiological cell Na+ and plasma K+ levels.(ABSTRACT TRUNCATED AT 250 WORDS)
在盐敏感（DS）和盐抵抗（DR）的 Dahl 大鼠中，研究了从第 5 周（幼年）、第 12 周（成年）或第 23 周（老年）开始，给予高盐饮食（8%氯化钠）7 周后，血压对慢性高盐摄入的反应以及红细胞钠钾（Rb+）转运的动力学。在含有不同细胞内钠（Na+i，2 - 8 mmol/L 细胞）和细胞外 Rb+（Rb+o）的钠介质中，测定哇巴因敏感的 Rb+摄取和钠排出的动力学。此外，评估了呋塞米敏感的 Rb+摄取（与 Rb+o 有关）的动力学以及钠和 Rb+泄漏的程度。高盐饮食使幼年和成年 DS 大鼠血压升高，但老年 DS 大鼠未出现，尽管在所有高盐饮食的 DS 大鼠年龄组中红细胞钠略有增加。低盐饮食喂养的 DS 和 DR 大鼠中钠钾泵的动力学参数相似。盐性高血压 Dahl 大鼠红细胞中哇巴因敏感的转运速率未受抑制。除高盐饮食喂养的 DS 大鼠外，所有组中钠钾泵的最大速度（与 Na+i 有关）均随年龄显著降低。这被对 Na+i 亲和力随年龄的增加所补偿，因此在生理细胞钠和血浆钾水平下，幼年和老年大鼠的转运速率没有显著差异。（摘要截断于 250 字）
