The Ca/voltage-gated K large conductance (BK) channel b1 subunit is particularly abundant in vascular smooth muscle. By determining their phenotype, BK b1 allows the BK channels to reduce myogenic tone, facilitating vasodilation. The endogenous steroid lithocholic acid (LCA) dilates cerebral arteries via BK channel activation, which requires recognition by a BK b1 site that includes Thr169. Whe...

Ca(2+)-activated K(+) (BK) channels in GH(3) cells are activated by arachidonic acid (AA). Because cytosolic phospholipase A(2) can produce other unsaturated free fatty acids (FFA), we examined the effects of FFA on BK channels in excised patches. Control recordings were made at several holding potentials. The desired FFA was added to the bath solution, and the voltage paradigm was repeated. AA...

AIMS Caveolin-1 (Cav-1) interacts with large conductance Ca(2+)-activated potassium channels (BKCa) and likely exerts a negative regulatory effect on the channel activity. We investigated the role of Cav-1 in modulating BK(Ca) channel-mediated, endothelium-derived hyperpolarizing factor (EDHF)-dependent arteriolar dilation in normal condition and in an experimental model of obesity. METHODS A...

The medial prefrontal cortex (PFC) is involved in cognitive functions, which undergo profound changes during adolescence. This alteration of the PFC function derives from neuron activity, which, in turn, may depend on age-dependent properties and the expression of neuronal ion channels. BK-type channels are involved in controlling both the Ca(+) (+) ion concentration in the cell interior and ce...

Phosphoinositide 3-kinase (PI3-kinase) has been shown to link leptin receptor activation to stimulation of large conductance Ca-activated K (BK) channels and subsequent inhibition of hippocampal epileptiform-like activity. However, the downstream targets of PI3-kinase in this action of leptin are unknown. Here we show that BK channel activation by leptin is dependent on the actin cytoskeleton, ...

Alternative exon splicing and reversible protein phosphorylation of large conductance calcium-activated potassium (BK) channels represent fundamental control mechanisms for the regulation of cellular excitability. BK channels are encoded by a single gene that undergoes extensive, hormonally regulated exon splicing. In native tissues BK channels display considerable diversity and plasticity in t...

BK channels are critical regulators of neuronal activity, controlling firing, neurotransmitter release, cerebellar function, and BK channel mutations have been linked to seizure disorders. Modulation of BK channel gating is well characterized, regulated by accessory subunit interactions, intracellular signaling pathways, and membrane potential. In contrast, the role of intracellular trafficking...

We assessed the effect of epoxyeicosatrienoic acids (EETs) in intact mesenteric arteries and Ca(2+)-activated K(+) (BK(Ca)) channels of isolated vascular smooth muscle cells from control and insulin-resistant (IR) rats. The response to 11,12-EET and 14,15-EET was assessed in small mesenteric arteries from control and IR rats in vitro. Mechanistic studies were performed in endothelium intact or ...

The nuclear factor of activated T-cells (NFAT) is a Ca(2+)-dependent transcription factor that has been reported to regulate the expression of smooth muscle contractile proteins and ion channels. Here we report that large conductance Ca(2+)-sensitive potassium (BK) channels and voltage-gated K(+) (K(V)) channels may be regulatory targets of NFATc3 in urinary bladder smooth muscle (UBSM). UBSM m...

The Ca(2+)/voltage-gated K(+) large conductance (BK) channel β1 subunit is particularly abundant in vascular smooth muscle. By determining their phenotype, BK β1 allows the BK channels to reduce myogenic tone, facilitating vasodilation. The endogenous steroid lithocholic acid (LCA) dilates cerebral arteries via BK channel activation, which requires recognition by a BK β1 site that includes Thr1...