Human myometrial adrenergic receptors: identification of the beta-adrenergic receptor by (/sup 3/H)dihydroalprenolol binding

Journal Article · Mon Feb 15 00:00:00 EST 1982 · Am. J. Obstet. Gynecol.; (United States)

OSTI ID:5707847

Hayashida, D N; Leung, R; Goldfien, A; Roberts, J M

The radioactive beta-adrenergic antagonist (/sup 3/H) dihydroalprenolol (DHA) binds to particulate preparations of human myometrium in a manner compatible with binding to the beta-adrenergic receptor. The binding of DHA is rapid (attaining equilibrium in 12 minutes), readily reversible (half time = 16 minutes), high affinity (K/sub D/ = 0.50 nM), low capacity (Bmax = 70 fmoles/mg of protein), and stereoselective ((-)-propranolol is 100 times as potent as (+) -propranolol in inhibiting DHA binding). Adrenergic agonists competed for DHA binding sites in a manner compatible with beta-adrenergic interactions and mirrored ..beta../sub 2/ pharmacologic potencies: isoproterenol > epinephrine >> norepinephrine. Studies in which zinterol, a ..beta../sub 2/-adrenergic agonist, competed for DHA binding sites in human myometrial particulate indicated that at least 87% of the beta-adrenergic receptors present are ..beta../sub 2/-adrenergic receptors. Binding of DHA to human myometrial beta-adrenergic receptors provides a tool which may be used in the examination of gonadal hormonal modification of adrenergic response in human uterus as well as in the analysis of beta-adrenergic agents as potentially useful tocolytic agents.

• Research Organization: Univ. of California, San Francisco
• OSTI ID: 5707847
• Journal Information: Am. J. Obstet. Gynecol.; (United States), Vol. 142:4
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
BINDING ENERGY
RADIORECEPTOR ASSAY
UTERUS
RECEPTORS
BIOCHEMICAL REACTION KINETICS
CONTRACTION
MUSCLES
RESPONSE MODIFYING FACTORS
STEROID HORMONES
TISSUES
TRITIUM COMPOUNDS
BODY
ENERGY
FEMALE GENITALS
HORMONES
ISOTOPE APPLICATIONS
KINETICS
LABELLED COMPOUNDS
ORGANS
REACTION KINETICS
TRACER TECHNIQUES
550201* - Biochemistry- Tracer Techniques