By a News Reporter-Staff News Editor at Biotech Week -- Research findings on Proteins are discussed in a new report. According to news originating from Hamamatsu, Japan, by NewsRx correspondents, research stated, "A 'cocktail' approach, which involves simultaneous administration of multiple CYP-specific probes, concurrently detects the activity of multiple CYP enzymes. We developed and validated a rapid and selective LC-MS/MS method for determining the plasma concentrations of 5 CYP probe drugs and metabolites (caffeine/paraxanthine, CYP1A2 substrate; losartan/losartan carboxylic acid (E3174), CYP2C9 substrate; omeprazole/5-hydroxyomeprazole, CYP2C19 substrate; dextromethorphan/dextrorphan, CYP2D6 substrate; and midazolam/1'-hydroxymidazolam, CYP3A4 substrate) by single-step extraction, followed by a single LC-MS/MS run."
Our news journalists obtained a quote from the research from Hamamatsu University, "An Ostro ™ 96-well plate was used for extraction of CYP substrates and metabolites from human plasma and urine. Following optimization of the chromatographic conditions, all the peaks were well separated, and retention times ranged between 4.4 and 11.7 mm. The total run time for a single injection was within 13 min. The accuracy and precision values suggested that the assay had high accuracy and reliability in plasma and urine samples. No significant matrix interference was observed. To demonstrate the efficacy of this method, plasma and urine concentrations of 5 CYP probe substrates and their metabolites were determined after simultaneous oral administration of 5 drugs to 4 healthy volunteers. All the substrates and metabolites were detected over an 8h period, and the plasma concentrations of each substrate at 8h after administration were above the lower limit of quantification. Urine concentrations of drugs and their metabolic ratio were evaluated after the administration."
According to the news editors, the research concluded: "The advantage of our cocktail approach is that it enables in vivo assessment of the activity of various drug-metabolizing enzymes in a single assay."
For more information on this research see: Simultaneous LC-MS/MS Analysis of the Plasma Concentrations of a Cocktail of 5 Cytochrome P450 Substrate Drugs and Their Metabolites. Biological & Pharmaceutical Bulletin, 2014;37(1):18-25. Biological & Pharmaceutical Bulletin can be contacted at: Pharmaceutical Soc Japan, 2-12-15Shibuya, Shibuya-Ku, Tokyo, 150-0002, Japan (see also Proteins).
The news correspondents report that additional information may be obtained from S. Tanaka, Hamamatsu University, Sch Med, Dept. of Clin Pharmacol & Therapeut, Higashi Ku, Hamamatsu, Shizuoka 4313192, Japan. Additional authors for this research include S. Uchida, N. Inui, K. Takeuchi, H. Watanabe and N. Namiki.
Keywords for this news article include: Asia, Antiarrhythmic, Antihypertensive, Japan, Drugs, Therapy, Losartan, Hamamatsu, Cytochromes, Hemeproteins, Cardiovascular Agents, Angiotensin II Inhibitors, Angiotensin II Receptor Antagonist
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