Radioiodination of chicken luteinizing hormone without affecting receptor binding potency

Journal Article · Fri Dec 01 00:00:00 EST 1989 · Biology of Reproduction; (USA)

DOI:https://doi.org/10.1095/biolreprod41.6.1047· OSTI ID:7138016

Kikuchi, M; Ishii, S ^[1]

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1. Waseda Univ., Tokyo (Japan)

By improving the currently used lactoperoxidase method, we were able to obtain radioiodinated chicken luteinizing hormone (LH) that shows high specific binding and low nonspecific binding to a crude plasma membrane fraction of testicular cells of the domestic fowl and the Japanese quail, and to the ovarian granulosa cells of the Japanese quail. The change we made from the original method consisted of (1) using chicken LH for radioiodination that was not only highly purified but also retained a high receptor binding potency; (2) controlling the level of incorporation of radioiodine into chicken LH molecules by employing a short reaction time and low temperature; and (3) fractionating radioiodinated chicken LH further by gel filtration using high-performance liquid chromatography. Specific radioactivity of the final {sup 125}I-labeled chicken LH preparation was 14 microCi/micrograms. When specific binding was 12-16%, nonspecific binding was as low as 2-4% in the gonadal receptors. {sup 125}I-Labeled chicken LH was displaced by chicken LH and ovine LH but not by chicken follicle-stimulating hormone. The equilibrium association constant of quail testicular receptor was 3.6 x 10(9) M-1. We concluded that chicken LH radioiodinated by the present method is useful for studies of avian LH receptors.

• OSTI ID: 7138016
• Journal Information: Biology of Reproduction; (USA), Vol. 41:6; ISSN 0006-3363
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
LH
RECEPTORS
BIOCHEMICAL REACTION KINETICS
BIRDS
CELL MEMBRANES
CHICKENS
FRACTIONATION
FSH
IODINATION
IODINE 125
LIQUID COLUMN CHROMATOGRAPHY
RADIOIMMUNOASSAY
ANIMALS
BETA DECAY RADIOISOTOPES
BIOASSAY
CELL CONSTITUENTS
CHEMICAL REACTIONS
CHROMATOGRAPHY
DAYS LIVING RADIOISOTOPES
DIAGNOSTIC TECHNIQUES
ELECTRON CAPTURE RADIOISOTOPES
FOWL
GONADOTROPINS
HALOGENATION
HORMONES
IMMUNOASSAY
IMMUNOLOGY
INTERMEDIATE MASS NUCLEI
IODINE ISOTOPES
ISOTOPE APPLICATIONS
ISOTOPES
KINETICS
MEMBRANE PROTEINS
MEMBRANES
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
PEPTIDE HORMONES
PITUITARY HORMONES
PROTEINS
RADIOASSAY
RADIOIMMUNODETECTION
RADIOIMMUNOLOGY
RADIOISOTOPES
REACTION KINETICS
SEPARATION PROCESSES
TRACER TECHNIQUES
VERTEBRATES
550201* - Biochemistry- Tracer Techniques