Type I receptors in parotid, colon, and pituitary are aldosterone selective in vivo

Journal Article · Thu Oct 01 00:00:00 EDT 1987 · American Journal of Physiology; (USA)

OSTI ID:7018844

Sheppard, K; Funder, J W ^[1]

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1. Prince Henry's Hospital, Melbourne (Australia)

Previous in vivo studies have demonstrated that type I receptors in the rat kidney are aldosterone selective, whereas those in the hippocampus do not appear to discriminate between aldosterone and corticosterone. The authors have injected mature rats with ({sup 3}H)aldosterone or ({sup 3}H)corticosterone plus 100-fold excess of RU 28362, with or without unlabeled aldosterone or corticosterone, and compared type I receptor occupancy in two classic mineralocorticoid target tissues (parotid and colon) and in the pituitary. Mature rats were killed 10-180 min after tracer administration; ({sup 3}H)aldosterone was well taken up and retained in all tissues, whereas ({sup 3}H)corticosterone was significantly retained only in the pituitary 10 min after tracer administration. To assess a possible role for corticosterone-binding globulin (CBG) in conferring aldosterone specificity on type I receptors, 10-day-old rats (with very low levels of CBG) were similarly injected. In the colon and parotid, ({sup 3}H)aldosterone binding was at least an order of magnitude higher than that of corticosterone; in the pituitary aldosterone binding was approximately three times that of corticosterone. They interpret these data as evidence that in the parotid and colon type I receptors are aldosterone selective by a non-CBG-requiring mechanism, whereas in the pituitary there appear to be both aldosterone-selective and nonselective type I sites.

• OSTI ID: 7018844
• Journal Information: American Journal of Physiology; (USA), Journal Name: American Journal of Physiology; (USA) Vol. 253:4; ISSN 0002-9513; ISSN AJPHA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ADRENAL HORMONES
ALDEHYDES
ALDOSTERONE
ANIMALS
BIOCHEMISTRY
BODY
BRAIN
CENTRAL NERVOUS SYSTEM
CHEMISTRY
CORTICOSTEROIDS
CORTICOSTERONE
DIGESTIVE SYSTEM
ENDOCRINE GLANDS
GASTROINTESTINAL TRACT
GLANDS
GLUCOCORTICOIDS
HIPPOCAMPUS
HYDROGEN COMPOUNDS
HYDROXY COMPOUNDS
IN VIVO
INTESTINES
ISOTOPE APPLICATIONS
KETONES
KIDNEYS
LARGE INTESTINE
MAMMALS
MEMBRANE PROTEINS
MINERALOCORTICOIDS
NERVOUS SYSTEM
ORGANIC COMPOUNDS
ORGANS
PITUITARY GLAND
PREGNANES
PROTEINS
RADIORECEPTOR ASSAY
RATS
RECEPTORS
RODENTS
SALIVARY GLANDS
STEROIDS
TRACER TECHNIQUES
TRITIUM COMPOUNDS
VERTEBRATES