Effect of mefloquine, a gap junction blocker, on circadian period2 gene oscillation in the mouse suprachiasmatic nucleus Ex Vivo

Jinmi Koo, Han Kyoung Choe, Hee Dae Kim, Sung Kook Chun, Gi Hoon Son, Kyungjin Kim

Research output: Contribution to journalArticle

Abstract

Background: In mammals, the master circadian pacemaker is localized in an area of the ventral hypothalamus known as the suprachiasmatic nucleus (SCN). Previous studies have shown that pacemaker neurons in the SCN are highly coupled to one another, and this coupling is crucial for intrinsic self-sustainability of the SCN central clock, which is distinguished from peripheral oscillators. One plausible mechanism underlying the intercellular communication may involve direct electrical connections mediated by gap junctions. Methods: We examined the effect of mefloquine, a neuronal gap junction blocker, on circadian Period 2 (Per2) gene oscillation in SCN slice cultures prepared from Per2::luciferase (PER2::LUC) knock-in mice using a real-time bioluminescence measurement system. Results: Administration of mefloquine causes instability in the pulse period and a slight reduction of amplitude in cyclic PER2::LUC expression. Blockade of gap junctions uncouples PER2::LUC-expressing cells, in terms of phase transition, which weakens synchrony among individual cellular rhythms. Conclusion: These findings suggest that neuronal gap junctions play an important role in synchronizing the central pacemaker neurons and contribute to the distinct self-sustainability of the SCN master clock.

Original languageEnglish
Pages (from-to)361-370
Number of pages10
JournalEndocrinology and Metabolism
Volume30
Issue number3
DOIs
Publication statusPublished - 2015

Fingerprint

Mefloquine
Suprachiasmatic Nucleus
Gap Junctions
Electrical Synapses
Genes
Luminescent Measurements
Neurons
Phase Transition
Luciferases
Hypothalamus
Mammals

Keywords

  • Circadian rhythm
  • Gap junctions
  • Mefloquine
  • Per2
  • Real-time bioluminescence
  • Suprachiasmatic nucleus

ASJC Scopus subject areas

  • Endocrinology, Diabetes and Metabolism
  • Endocrinology

Cite this

Effect of mefloquine, a gap junction blocker, on circadian period2 gene oscillation in the mouse suprachiasmatic nucleus Ex Vivo. / Koo, Jinmi; Choe, Han Kyoung; Kim, Hee Dae; Chun, Sung Kook; Son, Gi Hoon; Kim, Kyungjin.

In: Endocrinology and Metabolism, Vol. 30, No. 3, 2015, p. 361-370.

Research output: Contribution to journalArticle

Koo, Jinmi ; Choe, Han Kyoung ; Kim, Hee Dae ; Chun, Sung Kook ; Son, Gi Hoon ; Kim, Kyungjin. / Effect of mefloquine, a gap junction blocker, on circadian period2 gene oscillation in the mouse suprachiasmatic nucleus Ex Vivo. In: Endocrinology and Metabolism. 2015 ; Vol. 30, No. 3. pp. 361-370.
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