Autoradiographic localization of relaxin binding sites in rat brain

Journal Article · Thu Aug 01 04:00:00 EDT 1991 · Proceedings of the National Academy of Sciences of the United States of America; (United States)

DOI:https://doi.org/10.1073/pnas.88.15.6413· OSTI ID:5229972

Osheroff, P L; Phillips, H S ^[1]

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1. Genentech, Inc., South San Francisco, CA (USA)

Relaxin is a member of the insulin family of polypeptide hormones and exerts its best understood actions in the mammalian reproductive system. Using a biologically active 32P-labeled human relaxin, the authors have previously shown by in vitro autoradiography specific relaxin binding sites in rat uterus, cervix, and brain tissues. Using the same approach, they describe here a detailed localization of human relaxin binding sites in the rat brain. Displaceable relaxin binding sites are distributed in discrete regions of the olfactory system, neocortex, hypothalamus, hippocampus, thalamus, amygdala, midbrain, and medulla of the male and female rat brain. Characterization of the relaxin binding sites in the subfornical organ and neocortex reveals a single class of high-affinity sites (Kd = 1.4 nM) in both regions. The binding of relaxin to two of the circumventricular organs (subfornical organ and organum vasculosum of the lamina terminalis) and the neurosecretory magnocellular hypothalamic nuclei (i.e., paraventricular and supraoptic nuclei) provides the anatomical and biochemical basis for emerging physiological evidence suggesting a central role for relaxin in the control of blood pressure and hormone release. They conclude that specific, high-affinity relaxin binding sites are present in discrete regions of the rat brain and that the distribution of some of these sites may be consistent with a role for relaxin in control of vascular volume and blood pressure.

• OSTI ID: 5229972
• Journal Information: Proceedings of the National Academy of Sciences of the United States of America; (United States), Journal Name: Proceedings of the National Academy of Sciences of the United States of America; (United States) Vol. 88:15; ISSN PNASA; ISSN 0027-8424
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ANIMALS
AUTORADIOGRAPHY
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOCHEMICAL REACTION KINETICS
BIOLOGICAL FUNCTIONS
BIOLOGICAL LOCALIZATION
BLOOD PRESSURE
BODY
BRAIN
CENTRAL NERVOUS SYSTEM
CHEMICAL COMPOSITION
DAYS LIVING RADIOISOTOPES
ISOTOPES
KINETICS
LIGHT NUCLEI
MAMMALS
MAN
MEMBRANE PROTEINS
NERVOUS SYSTEM
NUCLEI
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
ORGANS
PEPTIDES
PHOSPHORUS 32
PHOSPHORUS ISOTOPES
POLYPEPTIDES
PRIMATES
PROTEINS
RADIOISOTOPES
RATS
REACTION KINETICS
RECEPTORS
RODENTS
VERTEBRATES