2003 Fiscal Year Final Research Report Summary
A Research for L-type Calcium Channel Modulation by b2-adrenergic Stimulation
| Project/Area Number |
14570698
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Circulatory organs internal medicine
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| Research Institution | Teikyo University School of Medicine |
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Principal Investigator |
FURUKAWA Taiji Teikyo University, School of Medicine, Lecturer, 医学部, 講師 (70276731)
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| Project Period (FY) |
2002 – 2003
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| Keywords | calcium channel / beta receptor / GPT binding protein |
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| Research Abstract |
We measured the effects of beta-adrenergic stimulations on L-type calcium channel in Xenopus oocyte expression system. L-type calcium channel (alpha 1 C) was co-expressed with calcium channel alpha2, beta2a subunits and stimulatory GPT binding protein (Gs). Adenylate cyclase, beta2-adrenergic receptor and PKA binding protein (AKAP79) were also co-expressed in various combinations of these proteins. Membrane current through expressed calcium channel was measured by conventional two-microelectrodes voltage clamp methods. cDNA for these proteins were already cloned and we produced cRNA for each proteins using in-vitro-transcription method. Microinjections of the combination of various cRNA were performed, and measured the effect of beta-stimulation by isoproterenol on the modulation of membrane current amplitude. However, no combination of the protein re-constructs the beta-adrenergic stimulation of L-type calcium channel, which is common in both skeletal muscles and myocytes.
We changed the expressing alphal subunit of calcium channel from alphalC to alphalA (P/Q-type). We observed PKA stimulation of the channel, and Rp-cAMPS and H89, PKA inhibitory agents, decreased the membrane current. We are planning to investigate the structure-function relationships of the two alphal subunits.
During the investigation we measured the effect of numerous calcium channel antagonists using the same expression system. The results were published as the supported research.
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Research Products
(5 results)
