Pharmacokinetics and disposition of WR-1065 in the rhesus monkey

Journal Article · Tue May 01 04:00:00 EDT 1990 · Drug Metabolism and Disposition; (USA)

OSTI ID:6485572

Mangold, D J; Huelle, B K; Miller, M A; Geary, R S; Sanchez-Barona, D O; Swynnerton, N F; Fleckenstein, L; Ludden, T M ^[1]

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1. Southwest Research Institute, San Antonio, TX (USA)

The pharmacokinetics of WR-1065 (S-2-(3-aminopropylamino)ethanethiol) were investigated following iv, intraduodenal, and intraportal administrations in the rhesus monkey. Pharmacokinetic parameters were estimated by compartmental modeling of plasma concentration data from 10-min and 120-min iv infusions. Higher apparent volumes of distribution (Vc and Vss) and higher mean residence time (MRT) were observed at the slower infusion rate but a constant total dose. The values reflect a change in the distribution of WR-1065, possibly due to to saturation of binding in plasma and tissue. However, clearance remained unchanged. For a monkey administered approximately twice the 60 mg/kg dose infused over 120 min, data analysis indicates a disproportional increase in AUC and a substantial decrease in clearance. Low and erratic plasma concentrations of free drug (analytically determined without reductive cleavage) were observed following intraduodenal administration of WR-1065, demonstrating the drug's poor oral bioavailability. Results of intraduodenal administrations of radiolabeled drug indicated than an appreciable amount of the radiolabel in the dose reached the systemic circulation. However, after either intraduodenal or iv administration, only 31% of the AUC (radiolabel) could be accounted for as total (free and disulfide-bound) WR-1065 by specific analysis in separate experiments. Low levels of total cysteamine strongly suggest it to be a minor contributor to the disposition of the drug. Free WR-1065 AUC values following intraportal administration were similar to values obtained after iv administration.

• OSTI ID: 6485572
• Journal Information: Drug Metabolism and Disposition; (USA), Journal Name: Drug Metabolism and Disposition; (USA) Vol. 18:3; ISSN DMDSA; ISSN 0090-9556
• Country of Publication: United States
• Language: English

Related Subjects

550501* -- Metabolism-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
AMINES
ANIMALS
CHEMICAL REACTIONS
CLEARANCE
DISTRIBUTION
DISULFIDES
DRUGS
INJECTION
INTAKE
INTRAVENOUS INJECTION
ISOTOPE APPLICATIONS
ISOTOPES
MAMMALS
MEA
METABOLISM
MONKEYS
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
PRIMATES
RADIOISOTOPES
RADIOPROTECTIVE SUBSTANCES
REDOX REACTIONS
THIOLS
TISSUE DISTRIBUTION
TRACER TECHNIQUES
VERTEBRATES