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

J. Biol. Chem., Vol. 279, Issue 26, 27345-27356, June 25, 2004

This Article Full Text Full Text (PDF) All Versions of this Article: 279/26/27345    most recent M313575200v1 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 Kim, J. H. Articles by Kim, S. J. Search for Related Content PubMed PubMed Citation Articles by Kim, J. H. Articles by Kim, S. J. Social Bookmarking                      What's this?

Purinergic Receptors Coupled to Intracellular Ca²⁺ Signals and Exocytosis in Rat Prostate Neuroendocrine Cells^*

Jun Hee Kim, Joo Hyun Nam, Mean-Hwan Kim, Duk-Su Koh, So-Jung Choi¶, Soo Jeong Kim, Ji Eun Lee, Kyeong Min Min, Dae-Yong Uhm, and Sung Joon Kim||

From the Department of Physiology and Center for Molecular Medicine and the ^¶Department of Molecular and Cellular Biology, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Suwon 440-746 and the Department of Physics, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea

Rat prostate neuroendocrine cells (RPNECs) display a variety of ion channels and exhibit -adrenergic regulation of cytosolic Ca²⁺ concentration ([Ca²⁺])_c. In this study, purinergic regulation of [Ca²⁺]_c and exocytosis was investigated in freshly isolated single RPNECs showing chromogranin A immunoreactivity. The presence of P2X and P2Y receptors in RPNECs was verified by the transient activation of Ca²⁺-permeable cationic channels and the release of Ca²⁺ from intracellular stores by extracellular ATP, respectively. The transient inward cationic current was effectively activated by ,-methyleneadenosine 5'-triphosphate (,-MeATP) and blocked by 2',3'-O-(2,4,6-trinitrophenyl)adenosine 5'-triphosphate, suggesting the presence of a P2X₁ or P2X₃ subtype. For the release of stored Ca²⁺, ATP and UTP were equally potent, indicating the functional expression of the P2Y₂ or P2Y₄ subtype. The mRNAs for P2X₁ and P2Y₂ were confirmed from reverse transcription-PCR analysis of RPNECs. The application of ,-MeATP induced large and transient increases in [Ca²⁺]_c, which were not attenuated by the blockers of voltage-activated Ca²⁺ channels or by depleting intracellular Ca²⁺ stores, but were abolished by omitting extracellular Ca²⁺. The application of UTP increased [Ca²⁺]_c to 55% of the peak [Ca²⁺]_c induced by ,-MeATP. The application of ,-MeATP induced exocytotic responses of RPNECs as monitored by carbon fiber amperometry and capacitance measurements. To our interest, the application of UTP did not induce amperometric currents, but reduced the membrane capacitance, indicating a net endocytosis. From these results, we postulate that a sharp rise in [Ca²⁺]_c by the P2X-mediated Ca²⁺ influx is required for exocytosis, whereas the relatively slow release of stored Ca²⁺ induces endocytosis in RPNECs.

Received for publication, December 11, 2003 , and in revised form, April 5, 2004.

^* This work was supported by Grants 01-PJ1-PG3–21400-0019 and 03-PJ1-PG3–21400-0007 from the Korea Health 21 Research and Development Project, Ministry of Health and Welfare, Republic of Korea, and by Samsung Grant SBRI B-A3-102. The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.

^|| To whom correspondence should be addressed. Tel.: 82-31-299-6104; Fax: 82-31-299-6129; E-mail: sjoonkim{at}med.skku.ac.kr.

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

This article has been cited by other articles:

				G. Burnstock Physiology and Pathophysiology of Purinergic Neurotransmission Physiol Rev, April 1, 2007; 87(2): 659 - 797. [Abstract] [Full Text] [PDF]