title: Long-term facilitation of spontaneous calcium oscillations in astrocytes with endogenous adenosine in hippocampal slice cultures.
abstract: It is well established that astrocytes release gliotransmitters and moderate neuronal activity in the central nervous system via intracellular Ca(2+) dynamics. Astrocytic Ca(2+) oscillations are one type of spontaneous Ca(2+) mobilization that occurs in astrocytes. However, the modulation of spontaneous astrocytic Ca(2+) oscillations, especially in pathophysiological conditions, is not yet fully understood. Here, we demonstrate that activation of adenosine receptors induces a long-lasting increase in the frequency of astrocytic Ca(2+) oscillations in rat hippocampal slice cultures. The long-term facilitation of the frequency of Ca(2+) oscillations was mediated by endogenous adenosine generated via breakdown of extracellular ATP by ecto-ATPase. We also demonstrate that local tissue injury with ultraviolet irradiation can cause this long-term facilitation of Ca(2+) oscillations via endogenous adenosine. Our data suggest that endogenous adenosine is one of the modulators of spontaneous astrocytic Ca(2+) oscillations in the rat hippocampus, and may play a significant role in altered Ca(2+) dynamics in astrocytes observed during pathophysiological conditions.
authors.affiliation: Department of Pharmacology, Jikei University School of Medicine, 3-25-8 Nishi-shimbashi, Minato-ku, Tokyo 105-8461, Japan. m.kawamura@jikei.ac.jp
authors.forename: Masahito
authors.initials: M
authors.lastname: Kawamura
authors.forename: Masahiro
authors.initials: M
authors.lastname: Kawamura
mesh_terms: D000241:Adenosine / Q000494:pharmacology*; D000814:Aniline Compounds / Q000494:pharmacology; D000818:Animals; D001253:Astrocytes / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism*; D020013:Calcium Signaling; D002478:Cells, Cultured; D006624:Hippocampus / Q000166:cytology*; D051381:Rats; D018047:Receptors, Purinergic P1 / Q000378:metabolism; D014966:Xanthenes / Q000494:pharmacology
chemical_list: D000814:Aniline Compounds; C409648:Fluo 4; D018047:Receptors, Purinergic P1; D014966:Xanthenes; D000241:Adenosine; D002118:Calcium