High resolution proton nuclear magnetic resonance approach to the study of hepatocyte and drug metabolism. Application to acetaminophen

Journal Article · Sat Jun 01 04:00:00 EDT 1985 · Mol. Pharmacol.; (United States)

OSTI ID:5043423

Nicholson, J K; Timbrell, J A; Bales, J R; Sadler, P J

/sub 1/H spin echo NMR spectra of intact hepatocytes, isolated from rat liver, showed resonances for glucose, mobile fatty acids, and +N(CH/sub 3/)/sub 3/ groups including choline headgroups of phosphoglycerides. Spectra from extracts of the same cells contained many more well resolved resonances due to low Mr metabolites. These included signals for free amino acids, ketone bodies, glucose, lactate, and acetate. 1H NMR spectra from suspensions of intact hepatocytes incubated with acetaminophen showed no resonances for drug metabolites, although changes in sugar resonances were observed. However, spectra of extracts from acetaminophen-treated hepatocytes contained resonances for both acetaminophen itself and its major metabolites, the glucuronide and sulfate conjugates. Results on the extent of acetaminophen metabolism as measured by 1H NMR compared well with previously reported chromatographic studies. The rate of metabolism of acetaminophen by hepatocytes was much slower in /sup 2/H/sub 2/O buffer compared to H/sub 2/O buffer and selective deuteration of several metabolites including the ketone bodies, glucose, and acetaminophen glucuronide was observed. The deuteration of glucose C/sup 2/H appeared to be due to futile cycling of the glycolytic pathway to at least fructose 6-phosphate, and incorporation of deuterium by the enzyme phosphoglucoisomerase. This work demonstrates that 1H NMR studies of intact hepatocytes and cell extracts together can provide considerable insight into the metabolism of acetaminophen in vitro. Little pretreatment of samples is required, results can be obtained rapidly, and both normal and drug metabolites can be observed simultaneously. Similar studies should be applicable to a wide range of other drugs.

• OSTI ID: 5043423
• Journal Information: Mol. Pharmacol.; (United States), Journal Name: Mol. Pharmacol.; (United States) Vol. 6; ISSN MOPMA
• Country of Publication: United States
• Language: English

Related Subjects

550501* -- Metabolism-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ACETATES
ALCOHOLS
ALDEHYDES
AMINES
AMINO ACIDS
AMMONIUM COMPOUNDS
ANIMALS
ANTIPYRETICS
BARYONS
BIOCHEMICAL REACTION KINETICS
BODY
CARBOHYDRATES
CARBOXYLIC ACID SALTS
CARBOXYLIC ACIDS
CENTRAL NERVOUS SYSTEM DEPRESSANTS
CHOLINE
DEUTERIUM
DIGESTIVE SYSTEM
DRUGS
ELEMENTARY PARTICLES
ENZYMES
FERMIONS
GLANDS
GLUCOSE
HADRONS
HEXOSES
HYDROGEN ISOTOPES
HYDROXY COMPOUNDS
IN VITRO
ISOMERASES
ISOTOPES
KETONES
KINETICS
LACTATES
LIGHT NUCLEI
LIPOTROPIC FACTORS
LIVER
MAGNETIC RESONANCE
MAMMALS
METABOLISM
METABOLITES
MONOSACCHARIDES
NUCLEAR MAGNETIC RESONANCE
NUCLEI
NUCLEONS
ODD-ODD NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANS
PROTONS
QUATERNARY COMPOUNDS
RATS
REACTION KINETICS
RESONANCE
RODENTS
SACCHARIDES
SPIN ECHO
STABLE ISOTOPES
VERTEBRATES