Effect of post-mortem time on. beta. -adrenergic receptor binding and adenylate cyclase activity

Conference · Fri Feb 28 23:00:00 EST 1986 · Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States)

OSTI ID:5386345

Vatner, D E; Knight, D; Young, M; Homcy, C J

The time between the death of an animal and the collection of tissue for ligand binding studies varies from study to study. The authors examined the effect of post-mortem time on ..beta..-adrenergic receptor, affinity, and adenylate cyclase activity. Five cows were sacrificed with an overdose of pentobarbital. The chest was opened and 40 gm sections of left ventricle were removed at 0 min, 30 min, 1 hr, and 2 hrs, and placed in iced saline for preparation of plasma membranes. ..beta..-Adrenergic receptor number, assayed with /sup 3/H-dihydroalprenolol, increased progressively over the 2 hr period from 91 +/- 4.2 to 173 +/- 18 fmol/mg protein, p < 0.01, while receptor affinity was unchanged (K/sub D/ = 7.7 +/- 1.4 to 6.7 +/- 1.1). Isoproterenol stimulated adenylate cyclase activity remained constant for 1/2 hr, and then declined from 167 +/- 51 to 20 +/- 5 pmol/min/mg protein at 2 hrs. Therefore, ..beta..-adrenergic receptor density increases over a 2 hr period after sacrifice, K/sub D/ remains constant and adenylate cyclase activity declines after 1/2 hr, suggesting that the increase in receptor number is not coupled to adenylate cyclase activity. These striking differences in results may explain variability in prior studies in which tissues were not collected and processed immediately post-mortem.

• Research Organization: Harvard Medical School, Boston, MA
• OSTI ID: 5386345
• Report Number(s): CONF-8604222-
• Journal Information: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States), Journal Name: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States) Vol. 45:3; ISSN FEPRA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
AFFINITY
ANIMALS
AUTONOMIC NERVOUS SYSTEM AGENTS
BIOCHEMICAL REACTION KINETICS
CATTLE
CYCLASES
DEATH
DOMESTIC ANIMALS
DRUGS
ENZYME ACTIVITY
ENZYMES
ISOTOPE APPLICATIONS
KINETICS
LABELLED COMPOUNDS
LIGANDS
LYASES
MAMMALS
MEMBRANE PROTEINS
ORGANIC COMPOUNDS
PROTEINS
REACTION KINETICS
RECEPTORS
RUMINANTS
SYMPATHOMIMETICS
TIME DEPENDENCE
TRACER TECHNIQUES
TRITIUM COMPOUNDS
VERTEBRATES