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Your search keyword '"Ohtsuka, Masanari"' showing total 3 results
Start Over Author "Ohtsuka, Masanari" Publisher elsevier
3 results on '"Ohtsuka, Masanari"'

1. Long-Term Two-Photon Calcium Imaging of Neuronal Populations with Subcellular Resolution in Adult Non-human Primates

Author

Sadakane, Osamu, Masamizu, Yoshito, Watakabe, Akiya, Terada, Shin Ichiro, Ohtsuka, Masanari, Takaji, Masafumi, Mizukami, Hiroaki, Ozawa, Keiya, Kawasaki, Hiroshi, Matsuzaki, Masanori, Yamamori, Tetsuo, Sadakane, Osamu, Masamizu, Yoshito, Watakabe, Akiya, Terada, Shin Ichiro, Ohtsuka, Masanari, Takaji, Masafumi, Mizukami, Hiroaki, Ozawa, Keiya, Kawasaki, Hiroshi, Matsuzaki, Masanori, and Yamamori, Tetsuo

Abstract

Two-photon imaging with genetically encoded calcium indicators (GECIs) enables long-term observation of neuronal activity invivo. However, there are very few studies of GECIs in primates. Here, we report a method for long-term imaging of a GECI, GCaMP6f, expressed from adeno-associated virus vectors in cortical neurons of the adult common marmoset (Callithrix jacchus), a small New World primate. We used a tetracycline-inducible expression system to robustly amplify neuronal GCaMP6f expression and up- and downregulate it for more than 100days. We succeeded in monitoring spontaneous activity not only from hundreds of neurons three-dimensionally distributed in layers 2 and 3 but also from single dendrites and axons inlayer 1. Furthermore, we detected selective activities from somata, dendrites, and axons in the somatosensory cortex responding to specific tactile stimuli. Our results provide a way to investigate the organization and plasticity of cortical microcircuits at subcellular resolution in non-human primates. Long-term two-photon calcium imaging has been challenging in non-human primates. Sadakane etal. use an inducible expression system to visualize cortical neurons in adult marmosets. They show that the same neuronal population can be followed over 100days and neuronal responses to tactile stimulation can be imaged at subcellular resolution.

Published
2015

2. Comparative analyses of adeno-associated viral vector serotypes 1, 2, 5, 8 and 9 in marmoset, mouse and macaque cerebral cortex.

Author

Watakabe A, Ohtsuka M, Kinoshita M, Takaji M, Isa K, Mizukami H, Ozawa K, Isa T, and Yamamori T

Subjects
Animals, Calcium-Calmodulin-Dependent Protein Kinase Type 2 genetics, Calcium-Calmodulin-Dependent Protein Kinase Type 2 metabolism, Callithrix, Cerebral Cortex cytology, Female, Genetic Vectors, Green Fluorescent Proteins genetics, Green Fluorescent Proteins metabolism, Macaca, Male, Mice, Inbred C57BL, Neurons metabolism, Promoter Regions, Genetic, Species Specificity, Synapsins genetics, Synapsins metabolism, Transduction, Genetic, Cerebral Cortex metabolism, Dependovirus genetics
Abstract

Here we investigated the transduction characteristics of adeno-associated viral vector (AAV) serotypes 1, 2, 5, 8 and 9 in the marmoset cerebral cortex. Using three constructs that each has hrGFP under ubiquitous (CMV), or neuron-specific (CaMKII and Synapsin I (SynI)) promoters, we investigated (1) the extent of viral spread, (2) cell type tropism, and (3) neuronal transduction efficiency of each serotype. AAV2 was clearly distinct from other serotypes in small spreading and neuronal tropism. We did not observe significant differences in viral spread among other serotypes. Regarding the cell tropism, AAV1, 5, 8 and 9 exhibited mostly glial expression for CMV construct. However, when the CaMKII construct was tested, cortical neurons were efficiently transduced (>∼70% in layer 3) by all serotypes, suggesting that glial expression obscured neuronal expression for CMV construct. For both SynI and CaMKII constructs, we observed generally high-level expression in large pyramidal cells especially in layer 5, as well as in parvalbumin-positive interneurons. The expression from the CaMKII construct was more uniformly observed in excitatory cells compared with SynI construct. Injection of the same viral preparations in mouse and macaque cortex resulted in essentially the same result with some species-specific differences., (Copyright © 2014 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.)

Published
2015
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3. PACAP decides neuronal laminar fate via PKA signaling in the developing cerebral cortex.

Author

Ohtsuka M, Fukumitsu H, and Furukawa S

Subjects
Animals, Brain-Derived Neurotrophic Factor pharmacology, Cell Cycle, Cerebral Cortex cytology, Cerebral Cortex enzymology, Cyclic AMP Response Element-Binding Protein metabolism, Cyclic AMP-Dependent Protein Kinases antagonists & inhibitors, Embryo, Mammalian drug effects, Gene Expression drug effects, Mice, Mice, Inbred Strains, Neurons enzymology, Phosphorylation, Pituitary Adenylate Cyclase-Activating Polypeptide pharmacology, Protein Kinase Inhibitors pharmacology, Signal Transduction, Stem Cells drug effects, Stem Cells physiology, Cerebral Cortex embryology, Cyclic AMP-Dependent Protein Kinases metabolism, Neurons physiology, Pituitary Adenylate Cyclase-Activating Polypeptide physiology
Abstract

Laminar formation in the developing cerebral cortex requires the precisely regulated generation of phenotype-specified neurons. To test the possible involvement of pituitary adenylate cyclase-activating polypeptide (PACAP) in this formation, we investigated the effects of PACAP administered into the telencephalic ventricular space of 13.5-day-old mouse embryos. PACAP partially inhibited the proliferation of cortical progenitors and altered the position and gene-expression profiles of newly generated neurons otherwise expected for layer IV to those of neurons for the deeper layers, V and VI, of the cerebral cortex. The former and latter effects were seen only when the parent progenitor cells were exposed to PACAP in the later and in earlier G1 phase, respectively; and these effects were suppressed by co-treatment with a protein kinase A (PKA) inhibitor. These observations suggest that PACAP participates in the processes forming the neuronal laminas in the developing cortex via the intracellular PKA pathway.

Published
2008
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