Lee S M, Schade S Z, Doughty C C
Biochim Biophys Acta. 1985 Sep 6;841(3):247-53. doi: 10.1016/0304-4165(85)90065-0.
NADPH and NADP+ levels were measured in rat lens from normal controls, from galactose-fed and diabetic rats during the first week of cataract formation. The level of NADPH in normal rat lens was determined to be 12.3 +/- 0.4 nmol/g wet weight, and that of NADP+ 4.6 +/- 0.2 nmol/g wet weight. In early cataract formation NADPH levels decreased rapidly during the first 2 days and then remained stable at 76% of control for galactose-fed and 84% for diabetic rats. NADP+ levels increased by 38% of control for galactose-fed and 54% for diabetic rats. Calculated NADPH/NADP+ ratios dropped from 3.36 +/- 0.21 to 1.86 +/- 0.16 in galactose fed rats, and from 2.81 +/- 0.15 to 1.61 +/- 0.16 in diabetic rats (P less than 0.001 for both experimental groups). These data are consistent with rapid NADPH oxidation during onset of lens cataracts. No significant changes in aldose reductase enzymatic activity levels were observed in either the galactosemic or the diabetic rats during the times measured.
在白内障形成的第一周，对正常对照组、喂食半乳糖的大鼠和糖尿病大鼠的晶状体中的还原型辅酶Ⅱ（NADPH）和氧化型辅酶Ⅱ（NADP⁺）水平进行了测量。正常大鼠晶状体中NADPH的水平测定为12.3±0.4 nmol/g湿重，NADP⁺的水平为4.6±0.2 nmol/g湿重。在白内障形成早期，NADPH水平在最初2天迅速下降，然后对于喂食半乳糖的大鼠保持在对照水平的76%，对于糖尿病大鼠保持在84%的稳定水平。NADP⁺水平对于喂食半乳糖的大鼠升高至对照水平的38%，对于糖尿病大鼠升高至54%。计算得出的NADPH/NADP⁺比值在喂食半乳糖的大鼠中从3.36±0.21降至1.86±0.16，在糖尿病大鼠中从2.81±0.15降至1.61±0.16（两个实验组的P均小于0.001）。这些数据与晶状体白内障发作期间NADPH的快速氧化一致。在所测量的时间段内，无论是半乳糖血症大鼠还是糖尿病大鼠，醛糖还原酶的酶活性水平均未观察到显著变化。
