Toshifumi Yamamoto

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Serotonergic axons from the raphe nuclei in the brainstem project to every region of the brain, where they make connections through their extensive terminal arborizations. This serotonergic innervation contributes to various normal behaviors and psychiatric disorders. The protocadherin-alpha (Pcdha) family of clustered protocadherins consists of 14(More)
The neuronal vesicular monoamine transporter (VMAT2) is the target molecule of action of some psychostimulants, such as methamphetamine and 3,4-methylenedioxymethamphetamine (MDMA). The present study examined the effect of antidepressants, such as selective serotonin reuptake inhibitors (SSRIs), on VMAT2 activity by measuring adenosine(More)
Our aim was to investigate whether a defect in vesicular monoamine transporter-2 (VMAT2) activities would affect dopaminergic cell functions or not. We examined mesencephalon dopaminergic cultures prepared from VMAT2 wild-type, heterozygous or homozygous knockout (KO) 14-day-old mouse fetuses to determine the number of tyrosine hydroxylase (TH)-positive(More)
Cocaine conditioned place preference (CPP) is intact in dopamine transporter (DAT) knockout (KO) mice and enhanced in serotonin transporter (SERT) KO mice. However, cocaine CPP is eliminated in double-KO mice with no DAT and either no or one SERT gene copy. To help determine mechanisms underlying these effects, we now report examination of baselines and(More)
Diverse protocadherins (Pcdhs), which are encoded as a large cluster (composed of alpha, beta and gamma clusters) in the genome, are localized to axons and synapses. The Pcdhs have been proposed to contribute to the generation of sophisticated neural networks and to regulate brain function. To address the molecular roles of Pcdhs in regulating individual(More)
The non-essential amino acid L-serine was shown to be required to support the survival of rat cerebellar Purkinje neurons because of lack of the expression of the L-serine biosynthesis enzyme 3-phosphoglycerate dehydrogenase in them. In the present study, we investigated L-[(3)H]serine uptake in primary cultures of neurons and astrocytes from the rat(More)
LMTK3 belongs to the LMTK family of protein kinases that are predominantly expressed in the brain. Physiological functions of LMTK3 and other members of the LMTK family in the CNS remain unknown. In this study, we performed a battery of behavioral analyses using Lmtk3(-/-) mice and showed that these mice exhibit abnormal behaviors, including pronounced(More)
Repeated amphetamine administration results in behavioral sensitization. Behavioral sensitization related to abuse and/or relapse may be associated with stable changes in gene expression. To explore the participating genes, we examined the changes in gene expression levels 24 h or 21 days (long-term withdrawal period) after chronic methamphetamine (METH)(More)
The actions of maitotoxin were studied using cultured brainstem cells and adrenal chromaffin cells. Maitotoxin induced a profound increase in the Ca2+ influx into cultured brainstem cells after a brief lag period. The maitotoxin-induced Ca2+ influx was suppressed by various voltage-dependent Ca2+ channel blockers such as Co2+, Mn2+, verapamil and diltiazem.(More)
Collapsin response mediator protein 1 (CRMP1) is one of the CRMP family members that are involved in various aspects of neuronal development such as axonal guidance and neuronal migration. Here we provide evidence that crmp1 (-/-) mice exhibited behavioral abnormalities related to schizophrenia. The crmp1 (-/-) mice exhibited hyperactivity and/or impaired(More)