Squid giant axons were internally dialyzed with a medium free of metabolic substrates but containing 45Ca buffered with EGTA to concentrations of free Ca++ in the range 0.01-230 muM. At (Ca)i of 1.0 muM OR GREATER, Ca efflux was in the range of 1-3 pmol/cm2 s, was dependent on (Na)o and (Ca)o, and was sensitive to membrane potential. At lower (Ca)i, the sensitivity of Ca efflux to membrane pote...

The C2 domain is a membrane-targeting domain found in many cellular proteins involved in signal transduction or membrane trafficking. The majority of C2 domains co-ordinate multiple Ca(2+) ions and bind the membrane in a Ca(2+)-dependent manner. To understand the mechanisms by which Ca(2+) mediates the membrane binding of C2 domains, we measured the membrane binding of the C2 domains of group I...

The intermediate (IK(Ca)) and small (SK(Ca)) conductance Ca(2+)-sensitive K(+) channels in endothelial cells (ECs) modulate vascular diameter through regulation of EC membrane potential. However, contribution of IK(Ca) and SK(Ca) channels to membrane current and potential in native endothelial cells remains unclear. In freshly isolated endothelial cells from mouse aorta dialyzed with 3 microM f...

In this study, membranes were prepared from hydrophilic cellulose acetate (CA) and antibacterial polyhexamethylene guanidine hydrochloride (PHMG) by phase inversion method to improve membrane separation antifouling capacities. The influence of preparation conditions on structure performance has been investigated evaluated. experimental results indicated that the CA have an asymmetric with a den...

Calcium (Ca(2+)) is a universal second messenger important for T lymphocyte homeostasis, activation, proliferation, differentiation, and apoptosis. The events surrounding Ca(2+) mobilization in lymphocytes are tightly regulated and involve the coordination of diverse ion channels, membrane receptors, and signaling molecules. A mechanism termed store-operated Ca(2+) entry (SOCE), causes depletio...

Blood fl ow is intimately linked to endothelial membrane potential and intracellular Ca 2+ levels ([Ca 2+ ] i ). Endothelial Ca 2+ infl ux appears to depend on the electrochemical gradient, and likely occurs through nonvoltage-dependent Ca 2+ entry pathways, possibly transient receptor potential (TRP) channels. Therefore, hyperpolarization of the endothelium membrane elevates [Ca 2+ ] i by an i...

TRPC1 (transient receptor potential canonical 1) is a Ca(2+)-permeable cation channel involved in diverse physiological function. TRPC1 may associate with other proteins to form a signaling complex, which is crucial for channel function. In the present study, we investigated the interaction between TRPC1 and large conductance Ca(2+)-sensitive K(+) channel (BK(Ca)). With the use of potentiometri...