Preface

　The present proceeding book entitled“ Biological Clocks: with special reference
to suprachiasmatic nucleus” is the 13th volume of Sapporo Symposium on Biological
Rhythm.　Sapporo Symposium on Biological Rhythm was founded in 1984 and
since then we organized the meetings biannually.　In associated with the symposium,
we celebrated the winner of Aschoff and Honma Prize for Biological Rhythm
Research.　The last two books were published by Aschoff and Honma Memorial
Foundation which is the successor of Honma Foundation of Life Science.
　This volume is consisted of the Winner’s lecture by Johanna H. Meijer and 16
articles in 5 chapters.　Johanna H. Meijer has been involved in neurophysiology of
the suprachiasmatic nucleus (SCN) and reported a number of new findings.　In
this book, she describes the circadian pacemaker in the SCN, which plays an important
role as an adaptive timekeeper for an ever changing environment.
　The first chapter focuses on the SCN functions in harmony with Johanna’s
lecture.　Daisuke Ono et al. emphasize differential roles of AVP and VIP signaling
in the developing SCN.　Tomoko Yoshikawa et al. report the localization of photoperiod
responsive circadian oscillators in the SCN.　Nana N. Takasu and Wataru
Nakamura note the role of entrainment of circadian pacemaker in the SCN output
for gonad function.　The second chapter deals with novel aspects of SCN function.　
Kazuhiro Yagita reports development of circadian oscillation and cellular differentiation.
　Shuji Akiyama et al. describe circadian clock system and mechanism of
oscillation in Cyanobacteria.　Hiromi Shimojo and Ryoichiro Kageyama note ultradian
oscillations in notch signaling during tissue morphogenesis.　John O’Neill et
al. emphasize a role of transmembrane magnesium transport in circadian timekeeping.
　The third chapter is focusing on the extra-SCN oscillatory system in
mammals.　Michihiro Mieda et al. emphasize the critical role of AVP neurons in
the circadian pacemaking.　Megumi Hatori reports light reception in the retina
and non-image forming visual response.　Yujiro Yamanaka et al. describe twooscillator
model of circadian system in humans.　Julie S. Pendergast and Shin
Yamazaki discuss the extra-SCN circadian pacemakers.　The chapter IV includes
physiological functions as integrated outputs of circadian clock.　Satoru Masubuchi
et al. report effect of hypoxia on circadian locomotor activity.　Satoru Koyanagi et
al. describe circadian rhythms in neuropathic pain hypersensitivity.　Ryosuke
Enoki et al. report imaging of circadian voltage rhythms in the SCN.　The chapter
V includes two papers from Honmas’ laboratory in Sapporo.　Shinya Nishide et al.
report dissociation of circadian Bmal1 and Per2 rhythms in the SCN and Aya
Honma et al. describe circadian rhythm in the nasal mucosa in allergic rhinitis.
　The most of these papers are in the very front of chronobiology and I hope you
enjoy them.
　September 10, 2017
                                                                                                                             Ken-ichi Honma
                                                                                                                                               Editor