Keiichi Nagata

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Mechanosensory channels of sensory cells mediate the sensations of hearing, touch, and some forms of pain. The TRPA1 (a member of the TRP family of ion channel proteins) channel is activated by pain-producing chemicals, and its inhibition impairs hair cell mechanotransduction. As shown here and previously, TRPA1 is expressed by hair cells as well as by most(More)
Varitint-waddler (Va and Va(J)) mice are deaf and have vestibular impairment, with inner ear defects that include the degeneration and loss of sensory hair cells. The semidominant Va mutation results in an alanine-to-proline substitution at residue 419 (A419P) of the presumed ion channel TRPML3. Another allele, Va(J), has the A419P mutation in addition to(More)
Neurons with the capacity to discharge at high rates--'fast-spiking' (FS) neurons--are critical participants in central motor and sensory circuits. It is widely accepted that K+ channels with Kv3.1 or Kv3.2 subunits underlie fast, delayed-rectifier (DR) currents that endow neurons with this FS ability. Expression of these subunits in heterologous systems,(More)
Severe myoclonic epilepsy in infancy (SMEI) is characterized by intractable febrile and afebrile seizures, severe mental decline, and onset during the first year of life. Nonsense, frameshift, and missense mutations of SCN1A gene encoding the voltage-gated Na(+) channel alpha-subunit type I (Na(v)1.1) have been identified in patients with SMEI. Here, we(More)
BACKGROUND We have previously reported that ethanol potentiates the acetylcholine-induced currents of the alpha4beta2 neuronal nicotinic acetylcholine receptors in rat cortical neurons and of those that are stably expressed in human embryonic kidney cells. The potentiation of the maximal currents evoked by high concentrations of acetylcholine suggests that(More)
BACKGROUND It is well established that neuronal nicotinic acetylcholine receptors (nAChRs) are sensitive to inhalational anesthetics. The authors previously reported that halothane potently blocked alpha4beta2-type nAChRs of rat cortical neurons. However, the effect of isoflurane, which is widely used clinically, on nAChRs largely remains to be seen. The(More)
Fipronil is the first phenylpyrazole insecticide introduced for pest control. Although fipronil is known to inhibit GABA receptors, the detailed mechanism of action remains to be seen. In order to elucidate the mechanism of fipronil interaction with the mammalian GABAA system, single-channel patch clamp experiments were performed using rat dorsal root(More)
Transient receptor potential (TRP) channels are attracting attention from various research areas including physiology, pharmacology and toxicology. Our group has focused on TRPA1 channels and revealed their expression pattern, ion channel kinetics and pharmacological characteristics. From Integrated Pest Management point of view, TRP channels could be a(More)
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