Ontogeny of specific prolactin binding sites in the rat choroid plexus and their temporal relation to the prolactin short-loop feedback system

Thesis/Dissertation · Tue Jan 01 04:00:00 EST 1985

OSTI ID:6067885

Silverman, F

The development of prolactin receptors in the choroid plexus of the rat was examined using the in vivo autoradiographic approach employing the principle of competitive binding. Animals aged 0, 10, 14, and 18 days postnatal were perfusion fixed following hormone injection and prepared for light microscopic autoradiography. The choroid plexus first demonstrated specific binding of prolactin at 14 days postnatal. The lactogen specificity of these binding sites was further defined by the ability of I/sup 125/-prolactin to be displaced by unlabelled human growth hormone, which is lactogenic in rats, and not by unlabelled insulin, which is structurally dissimilar to prolactin. Morphometric analysis was performed on electron micrographs of choroid plexus from 10 and 14 day postnatal rats. The volume densities of constituents known to be involved in the synthesis and/or function of polypeptide hormone receptors were measured and differences tested for statistical significance. A semi-quantitative histo-fluorescence technique was used to evaluate the ability of prolactin to stimulate secretion of its inhibiting factor, dopamine, in 10 day postnatal rats. The present findings indicate that the ontogenesis of specific prolactin binding sites is not temporally connected with the establishment of the prolactin short-loop feedback system since activation of the system occurs prior to the establishment of specific prolactin binding at choroid plexus.

• Research Organization: George Washington Univ., Washington, DC (USA)
• OSTI ID: 6067885
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ANIMALS
AUTORADIOGRAPHY
BETA DECAY RADIOISOTOPES
BIOCHEMICAL REACTION KINETICS
BIOLOGICAL FUNCTIONS
BODY
BRAIN
CENTRAL NERVOUS SYSTEM
DATA
DAYS LIVING RADIOISOTOPES
ELECTRON CAPTURE RADIOISOTOPES
EXPERIMENTAL DATA
FUNCTIONS
GONADOTROPINS
HORMONES
INFORMATION
INTERMEDIATE MASS NUCLEI
IODINE 125
IODINE ISOTOPES
ISOTOPES
KINETICS
LABELLED COMPOUNDS
LTH
MAMMALS
MEMBRANE PROTEINS
NERVOUS SYSTEM
NUCLEI
NUMERICAL DATA
ODD-EVEN NUCLEI
ONTOGENESIS
ORGANIC COMPOUNDS
ORGANS
PEPTIDE HORMONES
PITUITARY HORMONES
PROTEINS
RADIOISOTOPES
RATS
REACTION KINETICS
RECEPTORS
RODENTS
VERTEBRATES