通过胰岛素样生长因子（IGF）I放射免疫测定法、IGF-II放射受体测定法（RRA）以及酸乙醇提取后的增殖刺激活性RRA，测定胎鼠、新生鼠和母鼠血清中生长调节素相关肽。

Measurement of somatomedin-related peptides in fetal, neonatal, and maternal rat serum by insulin-like growth factor (IGF) I radioimmunoassay, IGF-II radioreceptor assay (RRA), and multiplication-stimulating activity RRA after acid-ethanol extraction.

作者信息

Daughaday W H, Parker K A, Borowsky S, Trivedi B, Kapadia M

出版信息

Endocrinology. 1982 Feb;110(2):575-81. doi: 10.1210/endo-110-2-575.

Abstract

Previous measurements of somatomedins (Sms) and insulin-like growth factors (IGFs) in maternal and fetal serum have yielded contradictory results. We have, therefore, measured maternal, fetal, and neonatal rat serum with two highly specific assays: 1) IGF-I/Sm-C RiA and 2) a highly specific IGF-II/rat placental membrane radioreceptor assay (RRA). In addition, we have made measurements with a less specific multiplication-stimulating activity (MSA)-rat placental membrane RRA. To avoid possible serious artifacts created by Sm-binding proteins, preliminary acid-ethanol extraction of serum was performed. Results are expressed in terms of a reference human serum with an assigned potency of 1 U/ml. Maternal RIA IGF-I fluctuated between 1.1-1.4 U/ml from the 17th day of pregnancy to the 25th day after delivery (nonpregnant rat serum pool, 1.25 +/- 0.22 U/ml). On day 21 of gestation, fetal serum radioimmunoassayable IGF-I was 1.03 +/- 0.03 U/ml. After birth, radioimmunoassayable IGF-I fell and reached .19 +/- 0.03 U/ml at 18 days of age, but rose to 0.71 +/- 0.04 U/ml at 25 days of age. At term, maternal radioreceptor assayable IGF-II was 2.18 +/- 0.27 U/ml (nonpregnant female pool, 1.4 +/- 0.12). By the 25th postpartum day, radioreceptor assayable IGF-II was 1.39 +/- 0.12 U/ml. Radioreceptor assayable IGF-II in fetal serum on day 19 was 3.26 +/- 0.48 U/ml and rose to 5.37 +/- 0.66 U/ml on the day of delivery. A further rise to 8.92 +/- 1.03 occurred on day 5. A subsequent fall to 2.41 +/- 0.05 U/ml was observed on day 25. The patterns of results of the MSA RRA in fetal and neonatal rat serum were similar to that obtained with the IGF-II RRA. We now conclude that radioimmunoassayable IGF-I is present in higher concentrations than previously reported in term fetal rat serum and that radioreceptor assayable IGF-II is selectively elevated in rat fetal and neonatal life and may have unique metabolic and growth-promoting significance.U

摘要

以往对母体和胎儿血清中生长调节素（Sms）和胰岛素样生长因子（IGFs）的测量结果相互矛盾。因此，我们采用两种高度特异性的检测方法对孕鼠、胎鼠和新生鼠的血清进行了检测：1）IGF-I/Sm-C放射免疫分析（RiA）和2）高度特异性的IGF-II/大鼠胎盘膜放射受体分析（RRA）。此外，我们还用特异性较低的促增殖活性（MSA）-大鼠胎盘膜RRA进行了测量。为避免Sm结合蛋白可能产生的严重假象，对血清进行了初步酸乙醇提取。结果以指定效价为1 U/ml的参考人血清表示。母体RIA IGF-I在妊娠第17天至分娩后第25天之间波动于1.1 - 1.4 U/ml（未孕大鼠血清池，1.25±0.22 U/ml）。妊娠第21天时，胎鼠血清中可通过放射免疫分析检测到的IGF-I为1.03±0.03 U/ml。出生后，可通过放射免疫分析检测到的IGF-I下降，在18日龄时降至0.19±0.03 U/ml，但在25日龄时升至0.71±0.04 U/ml。足月时，母体可通过放射受体分析检测到的IGF-II为2.18±0.27 U/ml（未孕雌性大鼠血清池，1.4±0.12）。到产后第25天，可通过放射受体分析检测到的IGF-II为1.39±0.12 U/ml。妊娠第19天时，胎鼠血清中可通过放射受体分析检测到的IGF-II为3.26±0.48 U/ml，在分娩当天升至5.37±0.66 U/ml。出生后第5天进一步升至8.92±1.03 U/ml。在第25天观察到随后降至2.41±0.05 U/ml。胎鼠和新生鼠血清中MSA RRA的结果模式与IGF-II RRA的结果相似。我们现在得出结论，可通过放射免疫分析检测到的IGF-I在足月胎鼠血清中的浓度高于先前报道，并且可通过放射受体分析检测到的IGF-II在大鼠胎儿期和新生儿期选择性升高，可能具有独特的代谢和促生长意义。