Vásárhelyi B, Dobos M, Temesvári P, Abrahám C, Pintér S, Tulassay T
First Department of Pediatrics, Semmelweis Medical University, Budapest, Hungary.
Biol Neonate. 1998 Dec;74(6):445-50. doi: 10.1159/000014066.
The aim of our study was to determine whether the impairment of Na+/K+ pump is detectable in erythrocytes during hypoxia and reoxygenation. Acute asphyxia was induced in 10 newborn piglets for 1 h by bilateral pneumothorax. The Na+/K+-ATPase activity, Na+, K+ and ATP content of RBCs were determined in baseline condition (paO2: 60.4 +/- 9.3 mm Hg), at the end of the hypoxic period (1 h) (paO2: 30.2 +/- 10.3 mm Hg), then hourly during the reoxygenation phase (2, 3, 4 h) (paO2: 54.8 +/- 9.0, 56.1 +/- 8.7, 57.2 +/- 9.6 mm Hg). The Na+/K+-ATPase activity was constant during the first 3 h. However, it decreased at 4 h (676 +/- 168 versus baseline 833 +/- 141 U, p < 0.05). The highest ATP content was measured also at this point (4.32 +/- 0.57 versus baseline 3.27 +/- 0.45 mmol/l RBC, p < 0.01). The Na+ content was lower at 1 and 2 h (14.0 +/- 1.8; 13.8 +/- 1.2 versus baseline 15.7 +/- 1.2 mmol/100 g Hb, p < 0.05), but later it became normal. Plasma monovalent cationic levels and intracellular K+ content did not alter during the experiment. Our results indicate that the deterioration of enzyme activity occurs within the same time-frame that previously described morphological alterations in brain tissue develop, so the RBC Na+/K+-ATPase activity might reflect the progress of posthypoxial brain damage.
我们研究的目的是确定在缺氧和复氧过程中，红细胞中的钠钾泵损伤是否可检测到。对10只新生仔猪进行双侧气胸诱导急性窒息1小时。在基线状态（动脉血氧分压：60.4±9.3毫米汞柱）、缺氧期结束时（1小时）（动脉血氧分压：30.2±10.3毫米汞柱）以及复氧阶段（2、3、4小时）每小时（动脉血氧分压：54.8±9.0、56.1±8.7、57.2±9.6毫米汞柱）测定红细胞的钠钾-ATP酶活性、钠、钾和ATP含量。钠钾-ATP酶活性在前3小时保持恒定。然而，在4小时时降低（676±168对比基线833±141单位，p<0.05）。此时也测得最高的ATP含量（4.32±0.57对比基线3.27±0.45毫摩尔/升红细胞，p<0.01）。钠含量在1小时和2小时时较低（14.0±1.8；13.8±1.2对比基线15.7±1.2毫摩尔/100克血红蛋白，p<0.05），但之后恢复正常。实验过程中血浆单价阳离子水平和细胞内钾含量未改变。我们的结果表明，酶活性的恶化发生在先前描述的脑组织形态改变发展的同一时间范围内，因此红细胞钠钾-ATP酶活性可能反映缺氧后脑损伤的进展。
