Rabbit myocardial /sup 82/Rb kinetics and a compartmental model for blood flow estimation

Journal Article · Sat Apr 01 04:00:00 EST 1989 · Am. J. Physiol.; (United States)

OSTI ID:5989357

Huang, S C; Williams, B A; Krivokapich, J; Araujo, L; Phelps, M E; Schelbert, H R

Quantification of regional myocardial blood flow (MBF) with rubidium-82 (/sup 82/Rb) and positron emission tomography (PET) requires the validation of a tracer kinetic model that adequately describes the kinetics of /sup 82/Rb in tissue. We performed 134 /sup 82/Rb kinetic experiments in 24 isolated, arterially perfused rabbit interventricular septa at different flow rates (0.5-4.5 ml.min-1.g-1) and under the following conditions: varied concentrations of glucose (2.8-11 mM), insulin (0-5 mU/ml), and potassium (5-8 mM); varied pH (7.2-7.8); varied workload; and the addition of acetylstrophanthidin (1.0 microM). The measured /sup 82/Rb tissue time-activity curves consisted of two exponential components, with half times inversely related to MBF. The size of the slow component decreased as MBF increased (from 70% at 0.3 ml.min-1.g-1 to 30% at 2.0 ml. min-1.g-1). The kinetics were not strongly dependent on the conditions studied and were consistent with a compartmental model containing two communicating compartments. The volume of the fast exchangeable compartment and the transport rate constant from the fast to the slow compartment were found to be independent of MBF. Values of MBF were estimated with the compartmental model from /sup 82/Rb kinetics, and they correlated well with the directly measured MBF (r = 0.91; slope = 1.03).

• Research Organization: Univ. of California, Los Angeles (USA)
• OSTI ID: 5989357
• Journal Information: Am. J. Physiol.; (United States), Journal Name: Am. J. Physiol.; (United States) Vol. 256; ISSN AJPHA
• Country of Publication: United States
• Language: English

Related Subjects

550601* -- Medicine-- Unsealed Radionuclides in Diagnostics
62 RADIOLOGY AND NUCLEAR MEDICINE
ALDEHYDES
ALKALI METAL ISOTOPES
ALKALI METALS
ANIMAL TISSUES
ANIMALS
BETA DECAY RADIOISOTOPES
BETA-PLUS DECAY RADIOISOTOPES
BIOLOGICAL MODELS
BLOOD FLOW
BODY
CARBOHYDRATES
CARDIOVASCULAR SYSTEM
COMPUTERIZED TOMOGRAPHY
DIAGNOSTIC TECHNIQUES
ELECTRON CAPTURE RADIOISOTOPES
ELEMENTS
EMISSION COMPUTED TOMOGRAPHY
GLUCOSE
HEART
HEXOSES
HORMONES
HOURS LIVING RADIOISOTOPES
INSULIN
INTERMEDIATE MASS NUCLEI
ISOTOPES
MAMMALS
METALS
MINUTES LIVING RADIOISOTOPES
MONOSACCHARIDES
MUSCLES
MYOCARDIUM
NUCLEI
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
ORGANS
PEPTIDE HORMONES
PERFUSED TISSUES
POSITRON COMPUTED TOMOGRAPHY
POTASSIUM
RABBITS
RADIOISOTOPES
RUBIDIUM 82
RUBIDIUM ISOTOPES
SACCHARIDES
TISSUES
TOMOGRAPHY
VERTEBRATES