Toshio Narahashi

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TTX-sensitive (TTX-S) and TTX-resistant (TTX-R) sodium channel currents were analyzed in acutely dissociated dorsal root ganglion (DRG) neurons isolated from 3-12-d-old and adult rats. Currents were recorded using the whole-cell patch-clamp technique. TTX-R current was more likely to be present in younger animals (3-7 d), whereas TTX-S current was more(More)
Rat dorsal root ganglion neurons are endowed with tetrodotoxin-sensitive(TTX-S) and tetrodotoxin-resistant (TTX-R) sodium channels. The pyrethroid insecticides, which are known to keep sodium channels open for a prolonged period of time, cause differential effects on the two types of sodium channels. The whole-cell patch clamp experiments were performed(More)
Ethanol, at physiologically relevant concentrations, significantly enhanced high-affinity neuronal nicotinic acetylcholine receptor (NnAChR) currents insensitive to alpha-bungarotoxin (alpha-BuTX-ICs) in cultured rat cortical neurons in a fast and reversible manner, as determined by standard whole-cell patch-clamp recording techniques. The enhancement was(More)
1. Two types of voltage-sensitive calcium channels were identified and studied in the neuroblastoma cell line N1E-115. Calcium channel currents as carried by Ba2+ (50 mM) were recorded using the whole-cell variation of the patch-electrode voltage-clamp technique. 2. A transient (type I) inward Ba2+ current was evoked by a step depolarization from a holding(More)
This article summarizes the development of cellular neuropharmacology and neurotoxicology, based primarily on my own research. The progress of this field depends at least in part on the theoretical and technological developments of excitable cell physiology, biophysics, and biochemistry. First, a brief historical development is described. Second, my earlier(More)
General anesthetics are thought to act on both excitatory and inhibitory neuronal pathways at both post- and presynaptic sites. However, the literature in these regards is somewhat controversial. The aim of the present study was to reassess the relative importance of the various anesthetic actions using a common preparation. Rat cortical neurons in primary(More)
Most insecticides are neurotoxicants causing various forms of hyperexcitation and paralysis in animals. A variety of neuroreceptors and ion channels have been identified as the major target sites of these neurotoxic insecticides. This paper gives the highlights of some of the recent development in this area. Pyrethroids keep the sodium channel open for(More)
The effects of riluzole, a neuroprotective drug, on high voltage-activated (HVA) calcium channels of rat dorsal root ganglion neurons were studied using the whole-cell patch-clamp technique. Riluzole inhibited HVA calcium channel currents in a dose-dependent, time-dependent and reversible manner. The apparent dissociation constants for riluzole inhibition(More)
The pyrethroid insecticides are known to slow the kinetics of the activation and inactivation gates of sodium channels. This results in prolonged openings of individual sodium channels and prolonged flow of whole-cell sodium current, which in turn cause hyperexcitation in animals. The aim of the present study was to solve three important remaining(More)