As a mission to be the inter-university research institute, NIPS conducts joint studies with researchers from domestic or foreign universities and other research institutes. NIPS provides specialized equipment, large-scale equipment, and research facilities, and develops new equipment for morphological and functional 4D imagingｓ of various organs such as the brain.
MRI is an imaging technique that utilizes the nuclear magnetic resonance of the hydrogen atom. Not only to image the anatomical details of the brain, but MRI also allows exploring the neural substrates of human cognitive function by the visualization of the task-related changes in regional cerebral blood flow （functional MRI）. For over a decade, we have been working on a 3T MRI to investigate the higher brain function of a human (The first 3T machine installed in 2000 was shut down in 2018). To simultaneously measure the neural activities of two participants during their social interaction, we have recently installed a dual-functional MRI system with two 3T MRIs. Furthermore, an ultra-high field (7T) MRI system has been installed. In 2016 and 2017, cooperative study projects using a 7T machine were performed for the purpose of technical assessment and development. As we have confirmed stable operation in 2018, it is now fully provided for cooperative studies.
Electron cryomicroscope is an electron microscope developed for observing close-to-life state biological samples with a combination of rapid freezing and ice embedding sample preparation methods. Biological specimens up to 200 nm thicknesses can be observed with high-resolution and high-contrast. Ultrastructure analyses of protein molecules, viruses, bacteria, cultured cells, and frozen tissue sections are performed with this novel microscopic system.
Serial block-face scanning electron microscope（SBF-SEM） is an advanced 3-D nano-imaging equipment. Two different types of SBF-SEM are available; high-resolution and wide-area types. Resin-embedded biological specimens are sliced by a diamond knife equipped inside the chamber, and the block-face images are acquired by scanning electron microscopy （SEM）. 3-D structures of the specimens are finally reconstructed from the acquired serial block-face images. 3-D structures of large biological specimens like brain tissue can be visualized at the resolution of several nanometers.
Multi-photon excitation is a method to visualize living tissue by exciting the fluorescence molecules with the tightly focused near-infrared femtosecond pulse laser. Since the longer wavelength is used for multi-photon excitation, it has a superior deeper tissue penetration and reduced phototoxicity compared with single-photon excitation. Our 2-photon microscopes have the top-level specification for deep tissue imaging and can be applied to the imaging of neurons and glial cells in deep tissues such as the mouse brain. Recently, we also developed a 2-photon fluorescence imaging microscope that can be applied to image protein-protein interaction and the protein activity.
We analyze the following physiological parameters in mice and rats:
1） Single unit recording from motor-related brain regions in the awake state,
2）Measurement of energy intake and expenditure in free-moving mice,
3） Measurement of body temperature, heart rate and blood pressure in free-moving mice,
4） Non-invasive echo-graphic imaging for evaluation of tissue structure-function relationships (liver, kidney and blood vessels), 4-dimensional changes in cardiac functions, and capillary blood flow (brain and umbilical cord) in anesthetized mice,
5） Mouse temperature preference assay with thermal gradient ring,
6) Behavioral analysis associated with emotions, memory and learning: Open field, Light-dark transition, Elevated plus maze, Forced swimming, Rota-rod, Passive avoidance, Fear conditioning, Morris water maze, Barnes circular maze, etc.