[1] Acad Sci Czech Republ, Inst Physiol, CR-14220 Prague 4, Czech Republic
[2] Charles Univ, Fac Med 1, Inst Biol, Prague, Czech Republic
[3] Univ Utrecht, Fac Vet, Dept Lab Anim Sci, Utrecht, Netherlands
[4] Univ Calif San Francisco, Dept Lab Med, San Francisco, CA 94143 USA