HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Submit a Letter to Editor Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Ebihara, S. Articles by Shirato, K. Search for Related Content PubMed PubMed Citation Articles by Ebihara, S. Articles by Shirato, K. Social Bookmarking                      What's this?

Volume 272, Number 25, Issue of June 20, 1997 pp. 16023-16029
©1997 by The American Society for Biochemistry and Molecular Biology, Inc.

Role of Cyclic ADP-Ribose in ATP-activated Potassium Currents in Alveolar Macrophages

(Received for publication, February 28, 1997, and in revised form, April 14, 1997)

Satoru Ebihara , Tsukasa Sasaki , Wataru Hida , Yoshihiro Kikuchi , Takako Oshiro , Sanae Shimura , Shin Takasawa ^¶ , Hiroshi Okamoto ^¶ , Akinori Nishiyama , Norio Akaike ^** and Kunio Shirato

From the  First Department of Internal Medicine, the ^¶ Department of Biochemistry, and the  First Department of Physiology, Tohoku University School of Medicine, Sendai 980-77 and the ^** Department of Physiology, Faculty of Medicine, Kyushu University, Fukuoka 812-82, Japan

There is growing evidence that extracellular ATP causes a dramatic change in the membrane conductance of a variety of inflammatory cells. In the present study, using the nystatin perforated patch recording configuration, we found that ATP (0.3-30 µM) induced a transient outward current in a concentration-dependent manner and that the reversal potential of the ATP-induced outward current was close to the K⁺ equilibrium potential, indicating that the membrane behaves like a K⁺ electrode in the presence of ATP. The first application of ATP to alveolar macrophages perfused with Ca²⁺-free external solution could induce the outward current, but the response to ATP was diminished with successive applications. Intracellular perfusion with a Ca²⁺ chelator, 1,2-bis(2-aminophenoxy)ethane-N,N,N,N-tetraacetic acid, also diminished the response. When cyclic ADP-ribose (cADPR) was applied to the macrophage cytoplasm, a transient outward current was elicited. Thereafter, the successive outward current was inhibited, suggesting the involvement of cADPR in the response. Intracellular perfusion with inositol 1,4,5-trisphosphate also induced a transient outward current, but the successive current was not inhibited. The ATP-induced outward current was abolished when 8-amino-cADPR (as a blocker of cADPR, 10⁶-10⁵ M) was introduced into the cytoplasm. Homogenates of alveolar macrophages showed both ADP-ribosyl cyclase and cADPR hydrolase activities, and CD38 (ADP-ribosyl cyclase/cADPR hydrolase) expression was confirmed by reverse transcriptase-polymerase chain reaction and Western blot analyses. These results indicate that ATP activates K⁺ currents by releasing Ca²⁺ from cADPR-sensitive internal Ca²⁺ stores.

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				K. Iizuka, A. Yoshii, K. Dobashi, T. Horie, M. Mori, and T. Nakazawa InsP3, but not novel Ca2+ releasers, contributes to agonist-initiated contraction in rabbit airway smooth muscle J. Physiol., September 15, 1998; 511(3): 915 - 933. [Abstract] [Full Text] [PDF]

				D. A. Cockayne, T. Muchamuel, J. C. Grimaldi, H. Muller-Steffner, T. D. Randall, F. E. Lund, R. Murray, F. Schuber, and M. C. Howard Mice Deficient for the Ecto-Nicotinamide Adenine Dinucleotide Glycohydrolase CD38 Exhibit Altered Humoral Immune Responses Blood, August 15, 1998; 92(4): 1324 - 1333. [Abstract] [Full Text] [PDF]

				S. Takasawa, T. Akiyama, K. Nata, M. Kuroki, A. Tohgo, N. Noguchi, S. Kobayashi, I. Kato, T. Katada, and H. Okamoto Cyclic ADP-ribose and Inositol 1,4,5-Trisphosphate as Alternate Second Messengers for Intracellular Ca2+ Mobilization in Normal and Diabetic beta -Cells J. Biol. Chem., January 30, 1998; 273(5): 2497 - 2500. [Abstract] [Full Text] [PDF]

				M.-K. Han, Y.-S. Cho, Y. S. Kim, C.-Y. Yim, and U.-H. Kim Interaction of Two Classes of ADP-ribose Transfer Reactions in Immune Signaling J. Biol. Chem., June 30, 2000; 275(27): 20799 - 20805. [Abstract] [Full Text] [PDF]