BACKGROUND The renal vasoconstrictor response to renal nerve stimulation is greater in congestive heart failure (CHF) rats than in control rats. This study tested the hypothesis that the enhanced renal vasoconstrictor response to renal nerve stimulation in CHF is a result of an impairment in the low-pass filter function of the renal vasculature. METHODS AND RESULTS In response to conventional...

Inhibitors of both phosphatidylinositol-3-kinase (PI3-kinase) and MAPK/ERK (mitogen-activate protein kinase/extracellular signal-related kinase) activation inhibit NMDA receptor-dependent long-term potentiation (LTP). PI3-kinase inhibitors also block activation of ERK by NMDA receptor stimulation, suggesting that PI3-kinase inhibitors block LTP because PI3-kinase is an essential upstream regula...

BackgroundElectrical stimulation in the kilohertz-frequency range has gained interest field of neuroscience. The mechanisms underlying this frequency range, however, are poorly characterized to date.Objective/hypothesisTo summarize manifold biological effects elicited by context currently existing literature and provide a mechanistic framework for neural responses observed range.MethodsA compre...

Two kinds of electrical stimulation, low frequency stimulation (5 Hz, 1 msec, 5 pulses, every 20 sec) and high frequency stimulation (30 Hz, 0.1 msec, 20 pulses, every 20 sec), produced contractions in isolated guinea-pig vas deferens. These responses were blocked by alpha, beta-methylene-ATP, but not prazosin. Phentolamine potentiated the contractions produced by low frequency stimulation, whi...

A two-interval forced-choice (2-IFC) tracking procedure was used to evaluate the effects of a 15-s pre-exposure to either 25 Hz or 200 Hz stimulation ("25 Hz or 200 Hz adaptation") on human vibrotactile frequency discrimination threshold (frequency DL/Weber fraction). Three subjects were studied. All stimuli (standard and comparison) were delivered to a central location on the thenar eminence o...

When the renal nerves are stimulated with sinusoidal stimuli over the frequency range 0.04-0.8 Hz, low (< or =0.4 Hz)- but not high (> or =0.4 Hz)-frequency oscillations appear in renal blood flow (RBF) and are proposed to increase responsiveness of the renal vasculature to stimuli. This hypothesis was tested in anesthetized rats in which RBF responses to intrarenal injection of norepinephrine ...

BACKGROUND High-frequency pallidal stimulation has been shown to improve various types of dystonia, including myoclonus-dystonia. CASE REPORT We report a case of epsilon sarcoglycan mutation-negative myoclonus-dystonia with response to low-frequency bilateral pallidal stimulation. DISCUSSION Low-frequency pallidal stimulation provides an effective means of treating various dystonias, regard...

The effect of endogenous serotonin on long-term potentiation (LTP) in region CAI was studied by blocking 5-HT2 receptors with ketanserin in rat hippocampal slices. Such a block significantly en-hanced long-term potentiation of the CAI population spike induced by high frequency stimulation of the schaffer collateral/ commissural pathway. This implies that serotonin acts on 5-HT2 receptors in CAI...

The effect of a non-symmetric waveform on nerve conduction block induced by high-frequency biphasic stimulation is investigated using a lumped circuit model of the unmyelinated axon based on Hodgkin-Huxley equations. The simulation results reveal that the block threshold monotonically increases with the stimulation frequency for the symmetric stimulation waveform. However, a nonmonotonic relati...