Estrogen effects on angiotensin receptors are modulated by pituitary in female rats

Journal Article · Thu Jan 01 04:00:00 EST 1987 · Am. J. Physiol.; (United States)

OSTI ID:6469572

Douglas, J G

The present studies were designed to test the hypothesis that changes in angiotensin II (ANG II) receptors might modulate the layered target tissue responsiveness accompanying estradiol administration. Estradiol was infused continuously in oophorectomized female rats. Aldosterone was also infused in control and experimental animals to avoid estrogen-induced changes in renin and ANG II. ANG II binding constants were determined in radioreceptor assays. Estradiol increased binding site concentration in adrenal glomerulosa by 76% and decreased binding sites of uterine myometrium and glomeruli by 45 and 24%, respectively. There was an accompanying increase in the affinity of ANG II binding to adrenal glomerulosa and uterine myometrium. Because estrogen is a potent stimulus of prolactin release from the pituitary of rodents, studies were also designed to test the hypothesis that prolactin may mediate some or all of the estrogen-induced effects observed. Hypophysectomy abolished estradiol stimulation of prolactin release and most ANG II receptor changes. Prolactin administration to pituitary intact rats was associated with a 50% increase in receptor density of adrenal glomerulosa simulating estradiol administration. However, the changes in glomeruli and uterine myometrium were opposite in that both tissues also increased receptor density, suggesting that prolactin was not the sole mediator of the estrogen-induced receptor changes. In conclusion, regulation of ANG II receptors in a number of diverse target tissues by estradiol is complex with contributions from estrogens and pituitary factors, which include but do not exclusively involve prolactin.

• Research Organization: Case Western Reserve Univ., Cleveland, OH
• OSTI ID: 6469572
• Journal Information: Am. J. Physiol.; (United States), Journal Name: Am. J. Physiol.; (United States) Vol. 252:1; ISSN AJPHA
• Country of Publication: United States
• Language: English

Related Subjects

550601* -- Medicine-- Unsealed Radionuclides in Diagnostics
62 RADIOLOGY AND NUCLEAR MEDICINE
ANGIOTENSIN
ANIMALS
BETA DECAY RADIOISOTOPES
BIOLOGICAL EFFECTS
BODY
CARDIOVASCULAR AGENTS
DAYS LIVING RADIOISOTOPES
DRUGS
ELECTRON CAPTURE RADIOISOTOPES
ENDOCRINE GLANDS
ESTROGENS
FEMALES
GLANDS
GLOBULINS
GONADOTROPINS
HORMONES
HYPOPHYSECTOMY
INTERMEDIATE MASS NUCLEI
IODINE 125
IODINE ISOTOPES
ISOTOPE APPLICATIONS
ISOTOPES
LTH
MAMMALS
MEDICINE
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
ORGANS
PEPTIDE HORMONES
PHYSIOLOGY
PITUITARY GLAND
PITUITARY HORMONES
PROTEINS
RADIOISOTOPES
RADIORECEPTOR ASSAY
RATS
RODENTS
STEROID HORMONES
SURGERY
TRACER TECHNIQUES
VASOCONSTRICTORS
VERTEBRATES