The Resting Potential and K Currents in Primary Human Articular Chondrocytes.

Human transplant programs provide significant opportunities for detailed assessments of physiological properties of selected tissues and cell types. We present a semi-quantitative study of the fundamental electrophysiological/biophysical characteristics of human chondrocytes, focused on K transport mechanisms, and their ability to regulate to the resting membrane potential, E. Patch clamp studies on these enzymatically isolated human chondrocytes reveal consistent expression of at least three functionally distinct K currents, as well as transient receptor potential (TRP) currents.

Preservation of cardiac function by prolonged action potentials in mice deficient of KChIP2.

Inherited ion channelopathies and electrical remodeling in heart disease alter the cardiac action potential with important consequences for excitation-contraction coupling. Potassium channel-interacting protein 2 (KChIP2) is reduced in heart failure and interacts under physiological conditions with both Kv4 to conduct the fast-recovering transient outward K(+) current (Ito,f) and with CaV1.2 to mediate the inward L-type Ca(2+) current (ICa,L).

Na(+) current expression in human atrial myofibroblasts: identity and functional roles.

In the mammalian heart fibroblasts have important functional roles in both healthy conditions and diseased states. During pathophysiological challenges, a closely related myofibroblast cell population emerges, and can have distinct, significant roles. Recently, it has been reported that human atrial myofibroblasts can express a Na(+) current, INa.