Decreased sodium-potassium pump activity in isolated hypertrophied feline ventricular myocytes.
Decreased sodium-potassium pump activity in isolated hypertrophied feline ventricular myocytes.
复制标题
分离的肥厚猫心室肌细胞中钠钾泵活性降低。
DOI：
10.1016/0024-3205(85)90427-8
复制
发表时间：
1985
期刊：
影响因子：
6.1
通讯作者：
S. Houser
中科院分区：
文献类型：
--
作者：
L. Silver;S. Houser
Na-K泵的活性在正常和肥大分离的猫肌细胞中通过测量瓦阿宾敏感的42- K摄取来评估。在成年猫的肺动脉周围放置一个收缩带，在猫的心肌中产生右心室肥厚。从带状和假手术动物的左、右心室分离出高产量的钙耐受肌细胞。正常（Na: 13.2; K: 133.4）和肥大（Na: 12.3; K: 127.5）肌细胞内钠（Na）和钾(K)浓度（mM）无显著差异（P < 0.05）。形态计量学分析显示，肥大肌细胞的宽度增加26%，体积增加42%，但两种细胞类型的肌节长度（1.9 μ）没有差异。在正常细胞（k=0.059； I=15.9）和肥大细胞（k=0.062； I=15.3）中，描述42-K摄取的速率常数（k, min - 1）和计算的总钾流入（I, pmol/cm2/sec）没有显著差异（P > 0.5）。在两种类型的细胞中，10−4M瓦巴因对钠钾泵活性的测量结果——钠钾敏感（活性）钾内流被最大程度地抑制。在这个浓度下，与对照组相比，肥厚肌细胞对瓦苦因敏感的钾摄取减少了23.5%。活性钾内流的减少可能是由于Na-K atp酶活性的降低和/或钠和钾沿着其电化学梯度的被动运动的减少。
The activity of the Na-K pump was assessed in normal and hypertrophied isolated feline myocytes by measuring ouabain-sensitive 42- K uptake. Right ventricular hypertrophy was produced in feline myocardium by placing a constricting band around the pulmonary artery of adult cats. High yields of calcium tolerant myocytes were isolated from the right and left ventricle of banded and sham operated animals. Intracellular sodium (Na) and potassium (K) concentrations (mM) were not significantly different (P > 0.5) in normal (Na: 13.2 ; K: 133.4) and hypertrophied (Na: 12.3 ; K: 127.5) myocytes. Morphometric analysis demonstrated a 26% increase in width and a 42% increase in volume of hypertrophied myocytes, however, the sarcomere length (1.9 μ) was not different in both cell types. The rate constant (k, min−1) describing 42-K uptake and the calculated total K influx (I, pmol/cm2/sec) were not significantly different (P > 0.5) in normal (k=0.059 ; I=15.9) and hypertrophied (k=0.062; I=15.3) cells. Ouabain-sensitive (active) K influx, a measure of Na-K pump activity, was maximally inhibited at 10−4M ouabain in both cell types. At this concentration, ouabain-sensitive K uptake was decreased 23.5% in hypertrophied myocytes compared to control. The decrease in active K influx may be due to a decrease in the activity of the Na-K ATPase and/or to a reduction in the passive movement of sodium and potassium down their electrochemical gradients.
肌球蛋白亚片段 1 在严格状态下与甘油化的昆虫飞行肌结合。
影响因子：
3.4
作者：
Goody,RS;Reedy,MC;Hofmann,W;Holmes,KC;Reedy,MK
通讯作者：
Reedy,MK