OBJECTIVE Citrate, potassium, and calcium levels in Viburnum opulus (V. opulus) and lemon juice were compared to evaluate the usability of V. opulus in mild to moderate level hypocitraturic stone disease. MATERIALS AND METHODS V. opulus and lemon fruits were squeezed in a blender and 10 samples of each of 100 ml were prepared. Citrate, calcium, sodium, potassium, magnesium, and pH levels in t...

Voltage-gated ion channels are important mediators of physiological functions in the central nervous system. The cyclic activation of these channels influences neurotransmitter release, neuron excitability, gene transcription, and plasticity, providing distinct brain areas with unique physiological and pharmacological response. A growing body of data has implicated ion channels in the susceptib...

To investigate the correlations among seminal plasma Magnesium (Mg), Phosphorus (P), Potassium (K), Calcium (Ca), Chromium (Cr), Manganese (Mn), Iron (Fe), Copper (Cu), Zinc (Zn), Selenium (Se), Molybdenum (Mo) and Iodine (I) concentrations and semen parameters [1– 15]. 500 fertile and 1000 infertile males provided a standardized semen specimen. Total Magnesium (Mg), Phosphorus (P), Potassium (...

PC12 cells, a clonal rat pheochromocytoma cell line, possess voltage-dependent calcium channels that bind the high affinity dihydropyridine calcium antagonist [3H]nitrendipine and other calcium channel blockers. The binding is temperature-dependent and saturable, and shows no cooperativity. The calcium antagonists inhibit potassium-induced 45Ca uptake into the cells with approximately the same ...

Caffeine increases resting calcium influx approximately threefold in normally polarized and in potassium-depolarized fibers of frog sartorius muscles. It does not affect the transient rapid increase in calcium influx that occurs at the beginning of a potassium depolarization. Calcium outflux in Ringer's solution, in zero calcium Ringer's solution, and in zero calcium Ringer's solution plus 0.00...

Acetylcholine elicited a sustained contraction and an increase in potassium efflux in longitudinal muscle isolated from the guinea pig ileum. Stepwise increases in the calcium concentration of the bathing medium, from 0.06 to 36 mM generally reduced the increase in potassium efflux, but had a complex effect on the mechanical response. Contractions produced by high levels of acetylcholine became...

Astrocytes express potassium and water channels to support dynamic regulation of potassium homeostasis. Potassium kinetics can be modulated by aquaporin-4 (AQP4), the essential water channel for astrocyte water permeability regulation. We investigated whether extracellular potassium ([K(+)](o)) can regulate astrocyte water permeability and the mechanisms of such an effect. Studies were performe...

We studied the effect of norepinephrine, calcium concentration, and rate of discharge in the presence of different |Ca * ],, on radioactive potassium movements in cardiac Purkinje fibers. The following results were obtained: (1) norepinephrine increases potassium uptake in quiescent fibers and in fibers driven at constant rate, but more in the latter; (2) norepinephrine also increases potassium...

Ionic currents underlie the firing patterns, excitability, and synaptic integration of neurons. Despite complete sequence information in multiple species, our knowledge about ion channel function in central neurons remains incomplete. This study analyzes the potassium currents of an identified Drosophila flight motoneuron, MN5, in situ. MN5 exhibits four different potassium currents, two fast-a...

We studied the effect of norepinephrine, calcium concentration, and rate of discharge in the presence of different [Ca2+]0 on radioactive potassium movements in cardiac Purkinje fibers. The following results were obtained: (1) norepinephrine increases potassium uptake in quiescent fibers and in fibers driven at constant rate, but more in the latter; (2) norepinephrine also increases potassium u...