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)

Journal Article · Mon Feb 01 04:00:00 EST 1982 · Endocrinology; (United States)

OSTI ID:5579229

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

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. We now conclude that radioimmunoassayable IGF-I is present in higher concentrations than previously reported interm fetal rat serum and that radioreceptor assayable IGF-II is selectively elevated in rat fatal and neonatal life and may have unique metabolic and rowth-promoting significance.

• Research Organization: Washington University School of Medicine, St. Louis, MO
• OSTI ID: 5579229
• Journal Information: Endocrinology; (United States), Journal Name: Endocrinology; (United States) Vol. 110:2; ISSN ENDOA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ANIMALS
BLOOD SERUM
EXTRACTION
FETUSES
GROWTH
ISOTOPE APPLICATIONS
MAMMALS
MEASURING METHODS
NEONATES
ORGANIC COMPOUNDS
PEPTIDES
PROTEINS
RADIOASSAY
RADIOIMMUNOASSAY
RADIORECEPTOR ASSAY
RATS
RODENTS
SEPARATION PROCESSES
STIMULATION
TRACER TECHNIQUES
VERTEBRATES