caa a22 4500 475818415 CHVBK 20180406123815.0 cr unu---uuuuu 170329e20000901xx s 000 0 eng 10.1007/s002280000168 doi (NATIONALLICENCE)springer-10.1007/s002280000168 Differential inhibition of hepatic and duodenal sulfation of (−)-salbutamol and minoxidil by mefenamic acid [Elektronische Daten] [M. Vietri, A. Pietrabissa, R. Spisni, F. Mosca, G. M. Pacifici] Objective: The aim of this investigation was to determine whether mefenamic acid and salicylic acid inhibit the sulfation of (−)-salbutamol and minoxidil in the human liver and duodenum, and if so, to ascertain whether the 50% inhibitory concentration (IC50) estimates are different in the two tissues. Methods: Sulfotransferase activities were measured for 10 mM (−)-salbutamol and 5 mM minoxidil, and the concentration of 3′-phosphoadenosine-5′-phosphosulphate-[35S] was 0.4 μM. Results: The IC50 estimates for (−)-salbutamol and minoxidil sulfation of mefenamic acid were 72 ± 5.4 nM and 1.5 ± 0.6 μM (liver), respectively, and 161 ± 23 μM and 420 ± 18 μM (duodenum), respectively. The figures for the liver were significantly lower (P < 0.0001) than those for the duodenum. The IC50 estimates for (−)-salbutamol sulfation of salicylic acid were 93 ± 11 μM (liver) and 705 ± 19 μM (duodenum, P < 0.0001). Salicylic acid was a poor inhibitor of minoxidil sulfation. Conclusion: The IC50 estimates for (−)-salbutamol sulfation of mefenamic acid and salicylic acid are lower than their unbound plasma concentrations after standard dosing, suggesting that mefenamic acid and salicylic acid should inhibit the hepatic sulfation of (−)-salbutamol in vivo. Springer-Verlag Berlin Heidelberg, 2000 Key words Sulfotransferase nationallicence Salbutamol nationallicence Minoxidil nationallicence Liver nationallicence Intestine nationallicence Vietri M. Department of Neurosciences, Section of Pharmacology, Medical School, Via Roma 55, I-56126 Pisa, Italy e-mail: pacifici@biomed.unipi.it, IT aut Pietrabissa A. Department of Oncology, Section of Surgery, Cisanello Hospital at University of Pisa, I-56124 Cisanello, Pisa, Italy, IT aut Spisni R. Department of Surgery, Medical School, Via Roma 67, I-56126 Pisa, Italy, IT aut Mosca F. Department of Oncology, Section of Surgery, Cisanello Hospital at University of Pisa, I-56124 Cisanello, Pisa, Italy, IT aut Pacifici G. M. Department of Neurosciences, Section of Pharmacology, Medical School, Via Roma 55, I-56126 Pisa, Italy e-mail: pacifici@biomed.unipi.it, IT aut https://doi.org/10.1007/s002280000168 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s002280000168 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Vietri M. Department of Neurosciences, Section of Pharmacology, Medical School, Via Roma 55, I-56126 Pisa, Italy e-mail: pacifici@biomed.unipi.it, IT aut NATIONALLICENCE 700 1- Pietrabissa A. Department of Oncology, Section of Surgery, Cisanello Hospital at University of Pisa, I-56124 Cisanello, Pisa, Italy, IT aut NATIONALLICENCE 700 1- Spisni R. Department of Surgery, Medical School, Via Roma 67, I-56126 Pisa, Italy, IT aut NATIONALLICENCE 700 1- Mosca F. Department of Oncology, Section of Surgery, Cisanello Hospital at University of Pisa, I-56124 Cisanello, Pisa, Italy, IT aut NATIONALLICENCE 700 1- Pacifici G. M. Department of Neurosciences, Section of Pharmacology, Medical School, Via Roma 55, I-56126 Pisa, Italy e-mail: pacifici@biomed.unipi.it, IT aut Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer