caa a22 4500 477057144 CHVBK 20180405111349.0 cr unu---uuuuu 170330e19960501xx s 000 0 eng 10.1007/s002280050095 doi (NATIONALLICENCE)springer-10.1007/s002280050095 Intraindividual variability in red blood cell thiopurine methyltransferase activity [Elektronische Daten] [T. Giverhaug, B. Klemetsdal, R. Lysaa, J. Aarbakke] Objective: Long-term (13 weeks) and circadian (24 hours) intraindividual variability in red blood cell (RBC) thiopurine methyltransferase (TPMT) activity in healthy subjects was studied. Methods: RBC TPMT activity was measured radiochemically. Results: The variability in RBC TPMT activity was low and was only slightly higher than the imprecision of the TPMT assay. Mean long-term intraindividual variability in RBC TPMT activity was 6.5% (CV) (n = 46). Mean intraindividual circadian variability in RBC TPMT activity was 6.4% (CV) (n = 18). Conclusions: In contrast to what has been observed in children with acute lymphoblastic leukaemia, the intra- individual variability in RBC TPMT activity in healthy subjects was low. The reported changes in baseline RBC TPMT activity in patients are probably therefore due to drugs, disease, assay variation or other, unidentified factors. Springer-Verlag Berlin Heidelberg, 1996 Key words Thiopurine methyltransferase (TPMT) nationallicence Leukaemia nationallicence circadian variation nationallicence 6-mercaptopurine nationallicence red blood cells nationallicence variability nationallicence azathioprine nationallicence Giverhaug T. Department of Pharmacology, Institute of Medical Biology, University of Tromsø, N-9037 Tromsø, Norway, NO aut Klemetsdal B. Department of Pharmacology, Institute of Medical Biology, University of Tromsø, N-9037 Tromsø, Norway, NO aut Lysaa R. Department of Pharmacology, Institute of Medical Biology, University of Tromsø, N-9037 Tromsø, Norway, NO aut Aarbakke J. Department of Pharmacology, Institute of Medical Biology, University of Tromsø, N-9037 Tromsø, Norway, NO aut https://doi.org/10.1007/s002280050095 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s002280050095 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Giverhaug T. Department of Pharmacology, Institute of Medical Biology, University of Tromsø, N-9037 Tromsø, Norway, NO aut NATIONALLICENCE 700 1- Klemetsdal B. Department of Pharmacology, Institute of Medical Biology, University of Tromsø, N-9037 Tromsø, Norway, NO aut NATIONALLICENCE 700 1- Lysaa R. Department of Pharmacology, Institute of Medical Biology, University of Tromsø, N-9037 Tromsø, Norway, NO aut NATIONALLICENCE 700 1- Aarbakke J. Department of Pharmacology, Institute of Medical Biology, University of Tromsø, N-9037 Tromsø, Norway, NO aut Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer