Time course of the estradiol-dependent induction of oxytocin receptor binding in the ventromedial hypothalamic nucleus of the rat

Journal Article · Fri Sep 01 00:00:00 EDT 1989 · Endocrinology; (USA)

DOI:https://doi.org/10.1210/endo-125-3-1414· OSTI ID:5607624

Johnson, A E; Ball, G F; Coirini, H; Harbaugh, C R; McEwen, B S; Insel, T R ^[1]

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1. National Institute of Mental Health, Poolesville, MD (USA)

Oxytocin (OT) transmission is involved in the steroid-dependent display of sexual receptivity in rats. One of the biochemical processes stimulated by the ovarian steroid 17 beta-estradiol (E2) that is relevant to reproduction is the induction of OT receptor binding in the ventromedial hypothalamic nucleus (VMN). The purpose of these experiments was to determine if E2-induced changes in OT receptor binding in the VMN occur within a time frame relevant to cyclic changes in ovarian steroid secretion. OT receptor binding was measured in the VMN of ovariectomized rats implanted for 0-96 h with E2-containing Silastic capsules. The rate of decay of OT receptor binding was measured in another group of animals 6-48 h after capsule removal. Receptors were labeled with the specific OT receptor antagonist ({sup 125}I)d(CH2)5(Tyr(Me)2,Thr4,Tyr-NH2(9))OVT, and binding was measured with quantitative autoradiographic methods. In addition, plasma E2 levels and uterine weights were assessed in animals from each treatment condition. Significant increases in E2-dependent OT receptor binding and uterine weight occurred within 24 h of steroid treatment. After E2 withdrawal, OT receptor binding and uterine weight decreased significantly within 24 h. These results are consistent with the hypothesis that steroid modulation of OT receptor binding is necessary for the induction of sexual receptivity.

• OSTI ID: 5607624
• Journal Information: Endocrinology; (USA), Journal Name: Endocrinology; (USA) Vol. 125:3; ISSN ENDOA; ISSN 0013-7227
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ANGIOTENSIN
ANIMALS
AUTORADIOGRAPHY
BETA DECAY RADIOISOTOPES
BIOCHEMICAL REACTION KINETICS
BODY
CARDIOVASCULAR AGENTS
DAYS LIVING RADIOISOTOPES
DRUGS
ELECTRON CAPTURE RADIOISOTOPES
ESTRADIOL
ESTRANES
ESTROGENS
FEMALE GENITALS
GLOBULINS
GONADS
HORMONES
HYDROXY COMPOUNDS
INTERMEDIATE MASS NUCLEI
IODINE 125
IODINE ISOTOPES
ISOTOPES
KINETICS
MAMMALS
MEMBRANE PROTEINS
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
ORGANS
OVARIES
OXYTOCIN
PEPTIDE HORMONES
PITUITARY HORMONES
PROTEINS
RADIOISOTOPES
RATS
REACTION KINETICS
RECEPTORS
RODENTS
STEROID HORMONES
STEROIDS
UTERUS
VASOCONSTRICTORS
VERTEBRATES
WEIGHT