Biologic stability of tauro-23-(/sup 75/Se) selena-25-homocholic acid

Journal Article · Mon Aug 01 04:00:00 EDT 1988 · J. Nucl. Med.; (United States)

OSTI ID:6924283

Monks, R; Boyd, G S

The stability of tauro-23-(/sup 75/Se)selena-25-homocholic acid (SeHCAT) towards deconjugation by the enzyme cholylglycine hydrolase was compared with that of taurocholate: whereas taurocholate underwent 58% deconjugation within 2 hr, SeHCAT suffered only 8% deconjugation plus 5% conversion to an unknown product within 24 hr. Incubation of SeHCAT under anaerobic conditions for 48 hr at 37 degrees C with human fecal organisms resulted in considerable deconjugation, 7 alpha-dehydroxylation, and dehydrogenation. Twenty-four hours after the simultaneous administration of SeHCAT and tauro-(24-/sup 14/C)cholate to a rabbit the recovery of /sup 75/Se in bile was 90% of that of /sup 14/C. Forty-eight hours following administration of SeHCAT to a second rabbit residual bile radioactivity revealed 80% deconjugation and dehydroxylation and 60% reconjugation with glycine. Although SeHCAT is more resistant than taurocholate towards modification by fecal bacterial enzymes, within the rabbit it follows the principal metabolic pathways of the natural bile acids.

• Research Organization: Amersham International Plc, Bucks (England)
• OSTI ID: 6924283
• Journal Information: J. Nucl. Med.; (United States), Journal Name: J. Nucl. Med.; (United States) Vol. 29:8; ISSN JNMEA
• Country of Publication: United States
• Language: English

Related Subjects

550601* -- Medicine-- Unsealed Radionuclides in Diagnostics
62 RADIOLOGY AND NUCLEAR MEDICINE
ANIMALS
BETA DECAY RADIOISOTOPES
BILE ACIDS
BIOLOGICAL MATERIALS
BIOLOGICAL WASTES
CARBON 14 COMPOUNDS
CARBOXYLIC ACIDS
CHEMICAL REACTIONS
DAYS LIVING RADIOISOTOPES
DECOMPOSITION
DRUGS
ELECTRON CAPTURE RADIOISOTOPES
ENZYMES
EVEN-ODD NUCLEI
FECES
HYDROLASES
HYDROLYSIS
HYDROXY COMPOUNDS
INTERMEDIATE MASS NUCLEI
ISOTOPE APPLICATIONS
ISOTOPES
LABELLED COMPOUNDS
LYSIS
MAMMALS
MATERIALS
METABOLISM
NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
RABBITS
RADIOISOTOPES
RADIOPHARMACEUTICALS
SELENIUM 75
SELENIUM ISOTOPES
SOLVOLYSIS
STABILITY
STEROIDS
STEROLS
TRACER TECHNIQUES
VERTEBRATES
WASTES