1. Using the single-electrode voltage clamp technique, three calcium current components were recorded at 35 degrees C from mouse dorsal root ganglion (DRG) neurones in culture. A transient low-threshold calcium current (T current) was recorded at clamp potentials (Vc) positive to -60 mV. Holding potentials (Vh) at or negative to -90 mV were required to fully remove inactivation. A large transie...

Calcium imaging using fura-2 and whole cell recording revealed the effective location of the oscillator mechanism on dopaminergic neurons of the substantia nigra, pars compacta, in slices from rats aged 15-20 days. As previously reported, dopaminergic neurons fired in a slow rhythmic single spiking pattern. The underlying membrane potential oscillation survived blockade of sodium currents with ...

Genetic hypertension results from numerous phenotypic expressions. We hypothesized that increased calcium current in vascular smooth muscle of genetically hypertensive animals is partly responsible for observed increases in agonist sensitivity, contractility, and calcium influx. Using adult, spontaneously hypertensive stroke-prone rats (SHRSP) and normotensive Wistar-Kyoto (WKY) controls from a...

Conflicting evidence has been obtained regarding whether transient receptor potential cation channels (TRPC) are store-operated channels (SOCs) or receptor-operated channels (ROCs). Moreover, the Ca/Na permeability ratio differs depending on whether the current-voltage (I-V) curve has a doubly rectifying shape or inward rectifying shape. To investigate the calcium permeability of TRPC4 channels...

Cerebellar Purkinje neurons have intrinsic membrane properties that favor burst firing, seen not only during complex spikes elicited by climbing fiber input but also with direct electrical stimulation of cell bodies. We examined the ionic conductances that underlie all-or-none burst firing elicited in acutely dissociated mouse Purkinje neurons by short depolarizing current injections. Blocking ...

introduction: the functional effects of orexin-b on the calcium spikes and excitability of the neuronal soma membrane of garden snail, helix aspersa were studied. methods: conventional intracellular recording, under the current clamp conditions was performed to examine the effects of orexin-b on the configuration and electrophysiological properties of calcium spikes. results: application of ore...

Pharmacologically distinct calcium channels have been characterized in dissociated cutaneous sensory neurons and motoneurons of the larval lamprey spinal cord. To enable cell identification, sensory dorsal cells and motoneurons were selectively labeled with fluorescein-coupled dextran amine in the intact spinal cord in vitro before dissociation. Calcium channels present in sensory dorsal cells,...

Calcium recommendations in North America set in 1997 were determined as the intake for maximal retention in age groups for which these data were available. Because there is a linear relationship between bone density and fracture risk and because 99% of calcium resides in the bone, it was thought that maximizing calcium retention is an optimal goal for bone health. Typically, data for only one g...

Previous studies have suggested the presence of different types of calcium channels in different regions of stomatogastric neurons. We sought to pharmacologically separate these calcium channel types. We used two different preparations from different regions of stomatogastric neurons to screen a range of selective calcium channel blockers. The two preparations were isolated cell bodies in cultu...