caa a22 4500 477057586 CHVBK 20180405111351.0 cr unu---uuuuu 170330e19960401xx s 000 0 eng 10.1007/s002280050073 doi (NATIONALLICENCE)springer-10.1007/s002280050073 Influence of renal failure on cytochrome P450 activity in hypertensive patients using a "cocktail” of antipyrine and nifedipine [Elektronische Daten] [V. L. Lanchote, W. C. Ping, S. R. C. J. Santos] Abstract.: Objective. Two substrates were coadministered in a "cocktail” approach to evaluate the contribution of renal failure to drug oxidation. Patients. Nineteen hypertensive patients, nine of them with chronic renal failure (CLCR 38.9 vs 102.3 ml⋅min−1⋅1.73 m−2), were investigated after peroral administration of a combination of antipyrine (500 mg, in capsules) and nifedipine (10 mg, in Oxcord capsules) in the morning after an overnight fast. Results. This "cocktail” approach made it possible to characterize in vivo the activities of different forms of cytochrome P450 in a single-study protocol using the total clearance of nifedipine and clearance for production of 3-hydroxymethylantipyrine (HMA), 4-hydroxyantipyrine (OHA) and norantipyrine (NORA). With this "cocktail” approach (antipyrine plus nifedipine), we can suggest a selective effect on the activities of cytochrome P450 forms associated with the formation of dehydronifedipine (P450 III A4) and of NORA in patients with mild renal failure under long-term antihypertensive therapy. Springer-Verlag Berlin Heidelberg, 1996 Key words Antipyrine-nifedipine cocktail nationallicence Renal failure nationallicence pharmacokinetics nationallicence patients nationallicence cytochrome P450 activity nationallicence Lanchote V. L. Faculty of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil, BR aut Ping W. C. University Hospital, University of São Paulo, São Paulo, Brazil, BR aut Santos S. R. C. J. 44 Dr. E. de Carvalho Aguiar Avenue, Advanced Center of Clinical Pharmacology and Therapeutics, Research Laboratory, First Floor, Heart Institute, University of São Paulo, São Paulo, 05403-000, Brazil, BR aut https://doi.org/10.1007/s002280050073 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s002280050073 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Lanchote V. L. Faculty of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil, BR aut NATIONALLICENCE 700 1- Ping W. C. University Hospital, University of São Paulo, São Paulo, Brazil, BR aut NATIONALLICENCE 700 1- Santos S. R. C. J. 44 Dr. E. de Carvalho Aguiar Avenue, Advanced Center of Clinical Pharmacology and Therapeutics, Research Laboratory, First Floor, Heart Institute, University of São Paulo, São Paulo, 05403-000, Brazil, BR aut Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer