Increased intracellular free Ca2+ concentrations elicit plasma membrane depolarization, which leads to the activation of K+ currents. However, the precise properties of K+ currents activated by depolarization in odontoblasts remain to be elucidated. The present study identified biophysical and pharmacological characteristics of time-dependent and voltage-activated K+ currents in freshly dissoci...

Patches of membrane on cells isolated from the nasal salt gland of the domestic duck typically contained two types of K+ channel. One was a large-conductance ("maxi") K+ channel which was activated by intracellular calcium and/or depolarizing membrane voltages, and the other was a smaller-conductance K+ channel which exhibited at least two conductance levels and displayed pronounced inward rect...

We studied the properties of voltage-activated outward currents in two types of spider cuticular mechanoreceptor neurons to learn if these currents contribute to the differences in their adaptation properties. Both types of neurons adapt rapidly to sustained stimuli, but type A neurons usually only fire one or two action potentials, whereas type B neurons can fire bursts lasting several hundred...

Type I putative magnocellular neurosecretory cells of the hypothalamic paraventricular nucleus (PVN) express a prominent transient outward rectification generated by an A-type potassium current. Described here is a slow transient outward current that alters cell excitability and firing frequency in a subset of type I PVN neurons (38%). Unlike most of the type I neurons (62%), the transient outw...

BACKGROUND Voltage-gated potassium (K(v)) channels are among the earliest ion channels to appear during brain development, suggesting a functional requirement for progenitor cell proliferation and/or differentiation. We tested this hypothesis, using human neural progenitor cells (hNPCs) as a model system. METHODOLOGY/PRINCIPAL FINDINGS In proliferating hNPCs a broad spectrum of K(v) channel s...

Isolated axons from the squid, Dosidicus gigas, were internally perfused with potassium fluoride solutions. Membrane currents were measured following step changes of membrane potential in a voltage-clamp arrangement with external isosmotic solution changes in the order: potassium-free artificial seawater; potassium chloride; potassium chloride containing 10, 25, 40 or 50, mM calcium or magnesiu...

The contribution of sympathetic constrictor impulses to arteriolar tone is now recognized as playing an important though sometimes variable role in the maintenance of increased peripheral resistance in some patients with hypertension. However, lack of a clear understanding of the exact nature of autonomic influences and of their importance in relation to other pressor factors has complicated th...

In man, C6, a new ganglionic blocking agent (50 mg. intravenously) produced inhibition of the Valsalva, tiltback and cold pressor vasopressor responses. Marked increases in digital blood flow and skin temperature with inhibition of digital reflexes to "noxious" stimuli were consistently observed (room temperature 70 F.). The increase in skin temperature was greater and more lasting than followi...

Surface temperature response to 15 agents was studied at 20 C. and 55 per cent humidity. Toe temperature was considered representative of the body's "glomus area." Temperatures at forehead and cheek represented the "blush area." Diethylaminoethanol, Hydergine, tetraethylammonium chloride, Priscoline, hexamethonium, Ilidar and Dibenzyline produced a prompt rise in temperature in the glomus area ...