Related Experiment Videos
Beta-adrenergic receptor function in cultured AT-1 cardiomyocytes
1Karolinska Institute Dept. of Medicine, Huddinge University Hospital, Sweden.
Biochemical and Biophysical Research Communications
|February 6, 1995
Summary
AT-1 cells, derived from mouse atrial tumors, possess functional beta-adrenergic receptors. These receptors regulate intracellular calcium and cAMP levels, making AT-1 cells a valuable tool for cardiac research.
Area of Science:
- Cardiology
- Molecular Pharmacology
- Cell Biology
Background:
- AT-1 cells are differentiated, contracting cardiomyocytes from transgenic mouse atrial tumors.
- Understanding beta-adrenergic receptor (BAR) function is crucial in cardiac physiology.
Purpose of the Study:
- To characterize BAR function in AT-1 cells.
- To investigate associated intracellular calcium regulation.
Main Methods:
- Equilibrium and competition binding assays using radioligands ([3H]-CGP-12177, CGP-20712A) to determine receptor subtype and density.
- Measurement of cAMP concentration following isoproterenol stimulation.
- Fluorimetric measurement of cytosolic calcium ([Ca2+]) oscillations in beating AT-1 cells.
Main Results:
- Predominantly beta 1-adrenoreceptors were identified (Kd = 0.30 nM, Bmax = 2.25 fmol/10(5) cells).
- Isoproterenol induced BAR down-regulation and increased cAMP levels.
- Isoproterenol enhanced cytosolic Ca2+ oscillation frequency, an effect blocked by alprenolol.
Conclusions:
- AT-1 cells exhibit functional beta-adrenergic receptor signaling pathways.
- These cells serve as a significant tool for studying cardiac biology and beta-adrenergic responses.