Some comments on the conductance of slow inward current in cardiac muscle

✍ Scribed by Alan Y.K. Wong

• Publisher: Springer
• Year: 1981
• Tongue: English
• Weight: 923 KB
• Volume: 43
• Category: Article
• ISSN: 1522-9602
• DOI: 10.1016/s0092-8240(81)90015-x

✦ Synopsis

Voltage clamp experiments, which determine the kinetic parameters of calcium conductance of cardiac muscle, (d,, f, , T,, and 7,) are analyzed with a generally accepted expression for slow inward current I,= &df (E -ER).

Activation (d) and inactivation (f ) reach the final values d, and & with time constants T,, and r, respectively. The analysis indicates that the measured f, agrees with the theoretical f,, but the measured d, differs from the theoretical d, by a factor which depends on fd. The peak tension can be made to correlate closely with the theoretical d, after a correction factor is applied to the raw measurements of activation.

It can be shown that experiments designed to measure T, can also be used to determine TV with greater accuracy.