Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
14
pubmed:dateCreated
1986-11-7
pubmed:abstractText
The pharmacokinetics and dynamics of the D- and L-isomers of the beta-adrenergic blocking agent penbutolol were investigated in healthy human volunteers. In Study One, subjects received a single 40-mg oral dose of L-penbutolol (the pharmacologically active stereoisomer), and matching placebo on two occasions. A mean peak serum penbutolol concentration of 268 ng/ml was reached at 0.9 h after dosing. Elimination half-life averaged 1.6 h, and total clearance 16.6 ml/min per kg body weight. Changes in blood pressure, ventricular rate, and rate of circumferential fiber shortening (Vcf) did not differ between L-penbutolol and placebo. In Study Two, subjects received 40 mg D-penbutolol, L-penbutolol, and placebo on three occasions. Total clearance of D-penbutolol was higher than for the L-isomer (43.7 vs 15.9 ml/min/kg; P less than 0.01); this was reflected in correspondingly increased area under the serum concentration curve for conjugates of the oxidized metabolite 4-hydroxy penbutolol (2.25 vs 0.66 micrograms/ml X h; P less than 0.005). In contrast, direct conjugates of L-penbutolol achieved higher serum concentrations than conjugates of D-penbutolol. Alterations in blood pressure, ventricular rate, and Vcf for D-penbutolol, L-penbutolol, and placebo were quantitatively small. Thus the clearance of penbutolol after oral administration in humans is stereoselective, but the oxidative pathway is more stereosensitive than the parallel conjugative pathway. Penbutolol causes minimal alterations in parameters of cardiac function after single 40-mg doses in healthy humans.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0023-2173
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
64
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
636-41
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1986
pubmed:articleTitle
Pharmacokinetics and dynamics of penbutolol in humans: evidence for pathway-specific stereoselective clearance.
pubmed:publicationType
Journal Article, Clinical Trial, Research Support, U.S. Gov't, P.H.S., Randomized Controlled Trial, Controlled Clinical Trial, Research Support, Non-U.S. Gov't