Development of receptors for insulin and insulin-like growth factor-I in head and brain of chick embryos: Autoradiographic localization

Journal Article · Wed Nov 01 00:00:00 EST 1989 · Endocrinology; (USA)

DOI:https://doi.org/10.1210/endo-125-5-2320· OSTI ID:5102238

Bassas, L; Girbau, M; Lesniak, M A; Roth, J; de Pablo, F ^[1]

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1. Hospital de la Santa Cruz y San Pablo, Barcelona (Spain)

In whole brain of chick embryos insulin receptors are highest at the end of embryonic development, while insulin-like growth factor-I (IGF-I) receptors dominate in the early stages. These studies provided evidence for developmental regulation of both types of receptors, but they did not provide information on possible differences between brain regions at each developmental stage or within one region at different embryonic ages. We have now localized the specific binding of (125I)insulin and (125I)IGF-I in sections of head and brain using autoradiography and computer-assisted densitometric analysis. Embryos have been studied from the latter part of organogenesis (days 6 and 12) through late development (day 18, i.e. 3 days before hatching), and the binding patterns have been compared with those in the adult brain. At all ages the binding of both ligands was to discrete anatomical regions. Interestingly, while in late embryos and adult brain the patterns of (125I)insulin and (125I) IGF-I binding were quite distinct, in young embryos both ligands showed very similar localization of binding. In young embryos the retina and lateral wall of the growing encephalic vesicles had the highest binding of both (125I)insulin and (125I)IGF-I. In older embryos, as in the adult brain, insulin binding was high in the paleostriatum augmentatum and molecular layer of the cerebellum, while IGF-I binding was prominent in the hippocampus and neostriatum. The mapping of receptors in a vertebrate embryo model from early prenatal development until adulthood predicts great overlap in any possible function of insulin and IGF-I in brain development, while it anticipates differential localized actions of the peptides in the mature brain.

• OSTI ID: 5102238
• Journal Information: Endocrinology; (USA), Vol. 125:5; ISSN 0013-7227
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
CHICKENS
ONTOGENESIS
GROWTH FACTORS
RECEPTORS
INSULIN
BIOLOGICAL LOCALIZATION
AUTORADIOGRAPHY
BIOCHEMICAL REACTION KINETICS
BRAIN
EMBRYOS
IODINE 125
LIGANDS
PEPTIDES
RETINA
SPECIFICITY
THERMODYNAMICS
TISSUE DISTRIBUTION
ANIMALS
BETA DECAY RADIOISOTOPES
BIRDS
BODY
BODY AREAS
CENTRAL NERVOUS SYSTEM
DAYS LIVING RADIOISOTOPES
DISTRIBUTION
ELECTRON CAPTURE RADIOISOTOPES
EYES
FACE
FOWL
HEAD
HORMONES
INTERMEDIATE MASS NUCLEI
IODINE ISOTOPES
ISOTOPES
KINETICS
MEMBRANE PROTEINS
MITOGENS
NERVOUS SYSTEM
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
ORGANS
PEPTIDE HORMONES
PROTEINS
RADIOISOTOPES
REACTION KINETICS
SENSE ORGANS
VERTEBRATES
550201* - Biochemistry- Tracer Techniques