Inhibition of voltage-sensitive calcium channels by the A(2A) adenosine receptor in PC12 cells
SCIE
SCOPUS
- Title
- Inhibition of voltage-sensitive calcium channels by the A(2A) adenosine receptor in PC12 cells
- Authors
- Park, TJ; Chung, SK; Han, MK; Kim, UH; Kim, KT
- Date Issued
- 1998-09
- Publisher
- LIPPINCOTT WILLIAMS & WILKINS
- Abstract
- The role of the A(2A) adenosine receptor in regulating voltage-sensitive calcium channels (VSCCs) was investigated in PC12 cells. Ca2+ influx induced by membrane depolarization with 70 mM K+ could be inhibited with CGS21680, an A(2A) receptor-specific agonist, Both L- and N-type VSCCs were inhibited by CGS21680 treatment. Effects of adenosine receptor agonists and antagonists indicate that the typical A(2A) receptor mediates inhibition of VSCCs. Cholera toxin (CTX) treatment for 24 h completely eliminated the CGS21680 potency. Similar inhibitory effects on VSCCs were obtained by membrane-permeable activators of protein kinase A (PKA). These effects were blocked by Rp-adenosine-3',5'-cyclic monophosphothioate, a PKA inhibitor. The data suggest that activation of the A(2A) receptor leads to inhibition of VSCCs via a CTX-sensitive G protein and PKA, ATP pretreatment caused a reduction in subsequent rise in cytosolic free Ca2+ concentration induced by 70 mM K+, presumably by inactivation of VSCCs. Simultaneous treatment with ATP and CGS21680 produced significantly greater inhibition of VSCCs than treatment with CGS21680 or ATP alone. Furthermore, the CGS21680-induced inhibition of VSCCs was not affected by the presence of reactive blue 2. CGS21680 still significantly inhibited ATP-evoked Ca2+ influx without VSCC activity after cobalt or 70 mM K+ pretreatment. These data suggest that the A(2A) receptor-sensitive VSCCs differ from those activated by ATP treatment. Although A, receptors induce inhibition of VSCCs as well as ATP-induced Ca2+ influx, the two inhibitory effects are clearly distinct from each other.
- Keywords
- A(2A) adenosine receptor; CGS21680; voltage-sansitive calcium channels; protein kinase A; cholera toxin-sensitive G protein; PC12 cells; ROOT GANGLION NEURONS; PROTEIN-KINASE-C; SYMPATHETIC NEURONS; N-TYPE; CA2+ CHANNELS; PERIPHERAL NEURONS; ADENYLATE-CYCLASE; BINDING PROTEIN; CA-2+ CHANNELS; HEART-CELLS
- URI
- https://oasis.postech.ac.kr/handle/2014.oak/20683
- DOI
- 10.1046/j.1471-4159.1998.71031251.x
- ISSN
- 0022-3042
- Article Type
- Article
- Citation
- JOURNAL OF NEUROCHEMISTRY, vol. 71, no. 3, page. 1251 - 1260, 1998-09
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- There are no files associated with this item.
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