Effect of methylprednisolone upon technetium-99m pyrophosphate assessment of myocardial necrosis in the canine countershock model

Journal Article · Thu Dec 01 04:00:00 EST 1977 · Circulation; (United States)

DOI:https://doi.org/10.1161/01.CIR.56.6.1029· OSTI ID:5111191

Schneider, R M; Hayslett, J P; Downing, S E; Berger, H J; Donabedian, R K; Zaret, B L

RRepeat DC countershock reproducibly results in myocardial necrosis in dogs. In this model, myocardial technetium-/sup 99m/ pyrophosphate (PYP) uptake correlates linearly with tissue creatine kinase depletion (r = -0.83). The effect of pretreatment with methylprednisolone (MP) was studied with PYP in 25 dogs. In myocardium damaged by countershock, 12 MP dogs had higher tissue radioactivity sample:normal (S:N) ratios than control (P < 0.05), suggesting increased tissue injury. However, by several other measures of tissue damage, the two groups did not differ. MP-elevated PYP S:N ratios were explained by reduced PYP activity in normal myocardium of MP dogs. Further experiments in 21 dogs revealed that renal PYP clearance, which correlated with glomerular filtration rate (GFR) as measured by creatinine clearance, was increased in MP dogs, resulting in accelerated urinary excretion of PYP (46.9 +- 3.6 vs 35.8 +- 2.4 percent injected dose in one hour, P < 0.01), and reduced blood PYP. Thus, MP does not modify countershock-induced myocardial injury. However, by increasing GFR, MP increased PYP excretion, resulting in lowered blood and normal zone myocardial PYP, thereby spuriously affecting myocardial PYP tissue uptake data.

• Research Organization: Yale Univ., New Haven
• OSTI ID: 5111191
• Journal Information: Circulation; (United States), Journal Name: Circulation; (United States) Vol. 56:6; ISSN CIRCA
• Country of Publication: United States
• Language: English

Related Subjects

560172* -- Radiation Effects-- Nuclide Kinetics &amp; Toxicology-- Animals-- (-1987)
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ADRENAL HORMONES
ANIMALS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOLOGICAL EFFECTS
BODY
CARDIOVASCULAR SYSTEM
CORTICOSTEROIDS
DISEASES
DOGS
GLUCOCORTICOIDS
HEART
HORMONES
HOURS LIVING RADIOISOTOPES
HYDROXY COMPOUNDS
INJURIES
INTERMEDIATE MASS NUCLEI
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
KETONES
MAMMALS
METABOLISM
MUSCLES
MYOCARDIUM
NECROSIS
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
ORGANS
OXYGEN COMPOUNDS
PATHOLOGICAL CHANGES
PHOSPHORUS COMPOUNDS
PREDNISOLONE
PREGNANES
PYROPHOSPHATES
RADIOISOTOPES
STEROID HORMONES
STEROIDS
TECHNETIUM 99
TECHNETIUM ISOTOPES
UPTAKE
VERTEBRATES
YEARS LIVING RADIOISOTOPES