Linked Life Data

4082636

Source:http://linkedlifedata.com/resource/pubmed/id/4082636

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
1986-1-24
pubmed:abstractText
The metabolic fate of [14C]ryosidine (ryodipine) has been investigated after oral administration to human subjects (by capsule), and to rats and dogs (in solution). The excretion patterns of 14C were similar for all three species: about 50% dose was excreted in urine, mainly in 24 h, but a proportion was excreted slowly, particularly by humans. Absorption in man appeared to be less than in the animal species, probably as a result of the capsule dosage form used. Mean concentrations of total 14C in human plasma reached a peak value of 0.41 microgram equiv./ml at four hours and declined biphasically thereafter (mean terminal t1/2 = 28 h). Unchanged ryosidine was only detected in plasma from two to six hours (mean t1/2 = 80 min), and never accounted for more than 5% of the plasma 14C. The extent of binding of ryosidine to the plasma proteins (in vitro) was similar (greater than 90%) to that of total 14C (in vivo; mainly metabolites). Less than 0.5% of the dose to human subjects was excreted via the kidneys as unchanged ryosidine, whereas the bulk of the extractable faecal 14C was in the form of unchanged drug and presumably represented unabsorbed material. The principal routes of biotransformation of ryosidine in all three species involved oxidative aromatization of the 1,4-dihydropyridine ring, followed by ester hydrolysis, O-dealkylation, hydroxylation of an alpha-methyl group (and lactonization) and some glucuronidation, although quantitative interspecies differences were apparent.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0049-8254
pubmed:author
pubmed:issnType
Print
pubmed:volume
15
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
965-77
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1985
pubmed:articleTitle
Metabolism and pharmacokinetics of the dihydropyridine calcium antagonist, ryosidine, in man.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't