Human myometrial adrenergic receptors during pregnancy: identification of the alpha-adrenergic receptor by (/sup 3/H) dihydroergocryptine binding

Journal Article · Mon Jul 15 00:00:00 EDT 1985 · Am. J. Obstet. Gynecol.; (United States)

DOI:https://doi.org/10.1016/S0002-9378(85)80046-6· OSTI ID:5098425

Jacobs, M M; Hayashida, D; Roberts, J M

The radioactive alpha-adrenergic antagonist (/sup 3/H) dihydroergocryptine binds to particulate preparations of term pregnant human myometrium in a manner compatible with binding to the alpha-adrenergic receptor (alpha-receptor). (/sup 3/H) Dihydroergocryptine binds with high affinity (KD = 2 nmol/L and low capacity (receptor concentration = 100 fmol/mg of protein). Adrenergic agonists compete for (/sup 3/H) dihydroergocryptine binding sites stereo-selectively ((-)-norepinephrine is 100 times as potent as (+)-norepinephrine) and in a manner compatible with alpha-adrenergic potencies (epinephrine approximately equal to norepinephrine much greater than isoproterenol). Studies in which prazosin, an alpha 1-antagonist, and yohimbine, and alpha 2-antagonist, competed for (/sup 3/H) dihydroergocryptine binding sites in human myometrium indicated that approximately 70% are alpha 2-receptors and that 30% are alpha 1-receptors. (/sup 3/H) dihydroergocryptine binding to human myometrial membrane particulate provides an important tool with which to study the molecular mechanisms of uterine alpha-adrenergic response.

• Research Organization: Univ. of California, San Francisco
• OSTI ID: 5098425
• Journal Information: Am. J. Obstet. Gynecol.; (United States), Journal Name: Am. J. Obstet. Gynecol.; (United States)
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
SYMPATHOMIMETICS
RECEPTORS
AFFINITY
BIOCHEMICAL REACTION KINETICS
CELL MEMBRANES
NORADRENALINE
PREGNANCY
TRACER TECHNIQUES
TRITIUM COMPOUNDS
UTERUS
ADRENAL HORMONES
AUTONOMIC NERVOUS SYSTEM AGENTS
BODY
CARDIOTONICS
CARDIOVASCULAR AGENTS
CELL CONSTITUENTS
DRUGS
FEMALE GENITALS
HORMONES
ISOTOPE APPLICATIONS
KINETICS
LABELLED COMPOUNDS
MEMBRANES
NEUROREGULATORS
ORGANS
REACTION KINETICS
STEROID HORMONES
550201* - Biochemistry- Tracer Techniques