Morphological and functional coupling of IP3 receptors with Na pumps in adrenal chromaffin cells
Project/Area Number |
13670050
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
General physiology
|
Research Institution | Fukuoka University |
Principal Investigator |
INOUE Masumi Fukuoka University, School of Medicine, Associate Professor, 医学部, 助教授 (40223276)
|
Co-Investigator(Kenkyū-buntansha) |
OGAWA Kouichi Fukuoka University, School of Medicine, Associate Professor, 医学部, 助教授 (60078780)
FUJISHIRO Naoji Fukuoka University, School of Medicine, Research assistant, 医学部, 助手 (30173420)
|
Project Period (FY) |
2001 – 2002
|
Project Status |
Completed (Fiscal Year 2002)
|
Budget Amount *help |
¥2,600,000 (Direct Cost: ¥2,600,000)
Fiscal Year 2002: ¥1,100,000 (Direct Cost: ¥1,100,000)
Fiscal Year 2001: ¥1,500,000 (Direct Cost: ¥1,500,000)
|
Keywords | Chromaffin cells / Ca store sites / Na pump / α subunit / Ca uptake / IP3 receptor / Catecholamine / secretion / ウァバイン / Ca動員取り込み |
Research Abstract |
Adrenal chromaffin cells are exposed to high concentrations of cortical hormones, one of which is ouabain-like substance. Thus, the effects of ouabain on catecholamine secretion and distribution of Na^+, K^+-ATPase α subunits in chromaffin cells were examined using amperometry and immunocytochemistry. While exposure to 1 μM ouabain did not have a marked effect on resulting secretion, it induced an increase in the secretion due to mobilization of partially stored Ca^<2+>. Immunocytochemistry revealed that Na^+, K^+-ATPase α1 subunit-like immunoreactivity (IR) was distributed ubiquitously at cell periphery, whereas α2-like IR were present at part of cell periphery. Inositol trisphosphate receptor (InsP_3R) type 2-like IR was distributed perinuclearly and in the vicinity of the plasma membrane, consistent with that of BODIPY-FL-InsP_3 binding. Peripheral BODIPY-FL-InsP_3 binding sites underlay membranes with α2-like IR, indicating that the peripheral InsP_3R type 2-containing Ca^<2+> storage was juxtaposed to membranes with the α2 subunit. This close association may account for the facilitation of Ca^<2+> uptake into stores and the consequent increase in mobilization-dependent secretion in the presence of 1 μM ouabain.
|
Report
(3 results)
Research Products
(8 results)