RT Journal Article
SR Electronic
T1 In vitro digitoxin metabolism. Rate-limiting step and alteration following spironolactone pretreatment.
JF Drug Metabolism and Disposition
JO Drug Metab Dispos
FD American Society for Pharmacology and Experimental Therapeutics
SP 635
OP 639
VO 13
IS 6
A1 W C Kershaw
A1 P Campbell
A1 G L Lage
YR 1985
UL http://dmd.aspetjournals.org/content/13/6/635.abstract
AB The biotransformation of digitoxin was considered as a linear transformation comprised of dual deoxy sugar cleavages culminating with product conjugation to glucuronic acid. Digitoxin and two metabolites, digitoxigenin bisdigitoxoside and digitoxigenin monodigitoxoside, were each incubated for 1 hr with rat liver slices. Measurements of amounts of various metabolites allowed determination of rate constants, showing the cleavage of the terminal sugar from digitoxigenin bisdigitoxoside to be the rate-limiting step. The inductive action of spironolactone predominately affected the rate-limiting step.