125I-Insulin Receptor Binding to Cord Blood Erythrocytes of Varying Gestational Age and Comparison with Adult Values
125I-Insulin Receptor Binding to Cord Blood Erythrocytes of Varying Gestational Age and Comparison with Adult Values
复制标题
不同胎龄脐带血红细胞的 125I-胰岛素受体结合及其与成人值的比较
作者：
Victoria L Herzberg;Mark J Boughter;Sandra K Carlisle;F. Ahmad;Donald E Hill
摘要：测定34例脐带血红细胞与~(125)I-胰岛素的结合率(%B/T=11.2±3.8)，与成人红细胞(%B/T=6.6±1.7)比较，差异有统计学意义。早产红细胞(%B/T=14.7±3.4)与足月红细胞(%B/T=10.1±3.2)相比，胰岛素结合量显著增加。胰岛素结合量与胎龄呈负相关(r=−0.613；P=0.001)，提示妊娠末期成人红细胞结合率较低。成人与足月脐血红细胞结合量的差异可能主要归因于每个细胞结合部位的不同。此外，早产儿与足月和成人红细胞相比，在亲和力和每个细胞的位置数量上都有很小的差异。推测：调控胰岛素从胰腺释放的机制在子宫内还不成熟。从胎儿胰腺直接释放到循环中的胰岛素可能与组织受体结合，与特定表面受体的亲和力和浓度有关，从而在细胞水平上为快速生长的胎儿组织提供直接控制。为此目的，红细胞受体可能起到运输胰岛素的作用。
Summary: The measurement of 125I-insulin binding to erythrocytes from 34 samples of cord blood (% B/T = 11.2 ± 3.8) showed statistically significant differences when compared to adult erythrocytes (% B/T = 6.6 ± 1.7). Preterm erythrocytes (% B/T = 14.7 ± 3.4) bound significantly more insulin when compared to term erythrocytes (% B/T = 10.1 ± 3.2). The negative correlation (r = −0.613; P = 0.001) between insulin binding and gestational age indicates that the trend during the final trimester of gestation is toward the lower binding observed for adult cells.The major differences in binding between adult and term cord blood erythrocytes may be primarily attributed to differences in the number of binding sites per cell. Additionally, there are small differences in both affinity and number of sites per cell in preterm as compared to term and adult erythrocytes.Speculation: The mechanisms governing insulin release from the pancreas are not mature in utero. Insulin released directly into the circulation from the fetal pancreas may be bound to tissue receptors in relation to the affinity and concentration of specific surface receptors, thereby, providing direct control at the cellular level for rapidly growing fetal tissues. Erythrocyte receptors may serve to transport insulin for this purpose.