Abstract
Magnesium ions play a fundamental role in cellular function, but the effects of changes in the concentration of intracellular ionized magnesium ([Mg2+](i)) on cell physiology have only recently received experimental attention. Increasing [Mg2+](i) from 0.3 to 3.0 mM in cardiac cells by internal perfusion has only small effects on the basal voltage-gated calcium current (I(Ca)) or on I(Ca) elevated by dihydropyridine calcium channel agonists. In contrast, I(Ca) elevated by cyclic adenosine monophosphate (cAMP)-dependent phosphorylation decreases by more than 50 percent. The effect of [Mg2+](i) is not due to changes in the concentration of cAMP or in the velocity of phosphorylation but rather appears to be a direct effect on the phosphorylated channel or on channel dephosphorylation.
| Original language | American English |
|---|---|
| Journal | Science |
| Volume | 239 |
| State | Published - Jan 1 1988 |
Keywords
- 8-Bromo Cyclic Adenosine Monophosphate
- Animal
- Calcium
- Cyclic AMP
- Heart
- Heart Ventricle
- In Vitro
- Ion Channels
- Isoproterenol
- Membrane Potentials
- Non-U.S. Gov't
- P.H.S.
- Ranidae
- Support
- U.S. Gov't
- calcium current
- cell culture
- heart muscle cell
- human
- magnesium
- phosphorylation
- short survey
Disciplines
- Circulatory and Respiratory Physiology