The prediction of plasma and brain levels of 2,3,5,6-tetramethylpyrazine following transdermal application
Journal Title: The AAPS Journal - Year 2002, Vol 4, Issue 4
Abstract
The purpose of this study was to construct a pharmacokinetic (PK) model and to determine PK parameters of 2,3,5,6-tetramethylpyrazine (TMP) after application of TMP transdermal delivery system. Data were obtained in Sprague-Dawley (SD) rats following a single dose of TMP transdermal delivery system. Blood samples were obtained at 0, 0.25, 0.5, 1, 2, 4, 6, 16, and 24 hours after the transdermal application. In the brain level study, 18 SD rats were divided into 6 groups. Three SD rats before and after transdermal application were culled and sacrificed at each of the following time intervals: 2, 4, 6, 16, and 24 hours after the TMP-TTS application. TMP concentrations in plasma and brain tissues were determined using high performance liquid chromatography and data were fitted using a zero-order absorption and a firstorder-elimination 3-compartment PK model. Fitted parameters included 2 volumes of distribution (V1, V2) and 2 elimination rate constants (k10, k20). The elimination half-life for TMP in plasma and brain was 26.5 and 31.2 minutes, respectively. The proposed PK model fit observed concentrations of TMP very well. This model is useful for predicting drug concentrations in plasma and brain and for assisting in the development of transdermal systems.
Authors and Affiliations
Xiaohong Qi, Chrisita Ackermann, Duxin Sun, Rong (Ron) Liu, Minli Sheng, Huimin Hou
Protein Binding of Antimicrobials: Methods for Quantification and for Investigation of its Impact on Bacterial Killing
Plasma protein binding of antimicrobial agents is considered to be a key characteristic of antibiotics as it affects both their pharmacokinetics and pharmacodynamics. However, up to the present, no standard methods for m...
Development of a Population Pharmacokinetic Model for Taranabant, a Cannibinoid-1 Receptor Inverse Agonist
Taranabant is a cannabinoid-1 receptor inverse agonist developed for the treatment of obesity. A population model was constructed to facilitate the estimation of pharmacokinetic parameters and to identify the influence o...
Levy G, Hayes B, “Physiochemical Basis of the Buffered Acetylsalicylic Acid Controversy New Engl. J. Med. 262:1053–1058 (1960)”—The Backstory
Dr. Levy is retired and can be reached through email.
Workshop Report: AAPS Workshop on Method Development, Validation, and Troubleshooting of Ligand-Binding Assays in the Regulated Environment
A novel format was introduced at the recent AAPS NBC Workshop on Method Development, Validation and Troubleshooting in San Diego on 18th May 2014. The workshop format was initiated by Binodh De Silva; Marie Rock and Sher...
UGT1A1 polymorphism predicts irinotecan toxicity: Evolving proof