A5027512669- Ion Transport and Channel Regulation
- Ion channel regulation and function
- Electrolyte and hormonal disorders
- Erythropoietin and Anemia Treatment
- Pluripotent Stem Cells Research
- Hair Growth and Disorders
- Cardiac Ischemia and Reperfusion
- Nerve injury and regeneration
- Neuroendocrine regulation and behavior
- Neurogenesis and neuroplasticity mechanisms
- Neuroscience and Neuropharmacology Research
- Anesthesia and Neurotoxicity Research
- Cardiac electrophysiology and arrhythmias
- Renal and related cancers
- Neuroscience and Neural Engineering
- Adenosine and Purinergic Signaling
- Nitric Oxide and Endothelin Effects
- Hormonal Regulation and Hypertension
- Renal function and acid-base balance
- Ion Channels and Receptors
- Cardiac Arrest and Resuscitation
- Tissue Engineering and Regenerative Medicine
- Circadian rhythm and melatonin
- Amino Acid Enzymes and Metabolism
- Inflammatory mediators and NSAID effects
Kitasato University
2015-2024
Tohoku University
2019-2020
The University of Tokyo
1981-2015
University of California, San Diego
2015
National Sagamihara Hospital
2012
Tokai University
2009
Massachusetts Institute of Technology
2005
AntiCancer (United States)
2005
Tokyo Institute of Technology
2003
Kobe University
1996
The hair follicle bulge area is an abundant, easily accessible source of actively growing, pluripotent adult stem cells. Nestin, a protein marker for neural cells, also expressed in cells and their immediate, differentiated progeny. fluorescent GFP, whose expression driven by the nestin regulatory element transgenic mice, served to mark cell fate. nestin-driven GFP are positive CD34 but negative keratinocyte keratin 15, suggesting relatively undifferentiated state. These can differentiate...
Abstract The optimal source of stem cells for regenerative medicine is a major question. Embryonic (ES) have shown promise pluripotency but ethical issues and potential to form teratomas. Pluripotent been produced from skin by either viral‐, plasmid‐ or transposon‐mediated gene transfer. These termed induced pluripotent iPS cells. may also malignant are inefficiently produced. not be suited individualized therapy, since they can undergo immunologic rejection. To address these fundamental...
A novel inwardly rectifying K+ channel, Kir7.1, with unique pore properties, was cloned recently. Working in the field of osmoregulation, we have also identified same human and rat channel found that is not only its sequence but dense localization follicular cells thyroid gland. Northern blot analysis revealed message abundantly expressed gland small intestine, moderately kidney, stomach, spinal cord brain. Immunohistochemistry thyroid, intestine choroid plexus demonstrated expression...
Sapecin B is structurally homologous to charybdotoxin (CTX), which found in scorpion venom. This study investigated the effects of sapecin on Ca(2+)-activated K+ currents [IK(Ca)] and rapidly inactivating clonal rat GH3 pituitary cells with whole cell voltage-clamp methods. (20 nM) reversibly blocked CTX-sensitive Ix(Ca) (the BK current) a dose-dependent manner, half-maximal inhibitory concentration approximately 0.9 nM, comparable that 0.08-0.4 nM for CTX. The Ca2+ cells, however, were not...
The neuropeptide hormone arginine-vasopressin (AVP) is well known to exert its antidiuretic effect via the vasopressin V2 receptor (V2R), whereas role of V1a (V1aR) in kidney remains be clarified. Previously, we reported decreased plasma volume and blood pressure receptor-deficient (V1aR-/-) mice (Koshimizu T, Nasa Y, Tanoue A, Oikawa R, Kawahara Kiyono Adachi Tanaka Kuwaki Mori T. Proc Natl Acad Sci USA 103: 7807-7812, 2006). In this study, investigated V1aR urine concentration, renal...
We have previously demonstrated that the neural stem-cell marker nestin is expressed in hair follicle stem cells located bulge area which are termed hair-follicle-associated pluripotent (HAP) cells. HAP from mouse and human could form spheres culture, spheres, keratin 15-negative CD34-positive differentiate to neurons, glia, keratinocytes, smooth muscle cells, melanocytes vitro. Subsequently, we nestin-expressing effect nerve spinal cord regeneration models. In present study, differentiated...
Potassium channels from the apical and basolateral membranes of Necturus proximal tubule were studied using patch-clamp technique. The conductance channel was dependent on pipette K+ concentration (apparent Km, 65.5 mM K+; maximum conductance, 49.8 pS). permeability ratio (PK+/PNa+) approximately 10:1. fractional open time increased with hyperpolarization, whereas mean times did not change. Ba2+ (0.1 concentration) blocked reduced time. activated depolarization had a slope 60 pS in...
Abstract Nestin‐positive, keratin 15 (K15)‐negative multipotent hair follicle stem cells are located above the bulge. We have termed this location pluripotent cell area. previously shown that transplantation of nestin‐expressing can regenerate peripheral nerve and spinal cord injuries. In present study, we regenerated impinged sciatic by transplanting cells. Human were transplanted around ICR nude (nu/nu) mice. The between fragments mouse where they differentiated into glial fibrillary...
Transgenic and knockout mice reveal a pathway that controls the extent of myelination by Schwann cells.
Inflammatory cytokines have been reported to contribute the progression of cardiac remodeling in various heart diseases and a remarkable prolongation monophasic action potential duration reductions expression Kv4.2 K+ channel-interacting protein-2 (KChIP-2) rat autoimmune myocarditis model documented. In this study, effect tumor necrosis factor-alpha (TNF-alpha) on cultured cardiomyocytes was evaluated, focusing change voltage-gated outward current related molecules.Cardiomyocytes isolated...
Abstract Objectives/Hypothesis: We examined whether sufficient water intake is effective in the long‐term control of vertigo and hearing activity patients with Meniere disease (MD) for whom conventional therapy has proven unsuccessful. Study Design: The authors conducted a time‐series study historical control. Methods: Eighteen MD group 1 drank 35 mL/kg per day 2 years. Twenty‐nine treated dietary diuretic more than years during 1992 to 1999 at same hospital were enrolled 2. Results:...
We have previously demonstrated that the neural stem-cell marker nestin is expressed in hair follicle stem cells. Nestin-expressing cells were initially identified bulge area (BA) using a transgenic mouse model which promoter drives green fluorescent protein (ND-GFP). The hair-follicle ND-GFP-expressing are keratin 15-negative and CD34-positive could differentiate to neurons, glia, keratinocytes, smooth muscle melanocytes vitro. Subsequently, we showed nestin-expressing affect nerve spinal...
Both aldosterone and luminal vasopressin may contribute to the maintenance of acid-base homeostasis, but functional relationship between these hormones is not well understood. The effects likely result from its interaction with V1a receptors on membranes intercalated cells in collecting duct. Here, we found that mice lacking receptor exhibit type 4 renal tubular acidosis. administration mineralocorticoid agonist fludrocortisone ameliorated acidosis by restoring excretion urinary ammonium via...
In development of the peripheral nervous system, Schwann cells proliferate, migrate, and ultimately differentiate to form myelin sheath. all myelination stages, continuously undergo morphological changes; however, little is known about their underlying molecular mechanisms. We previously cloned dock7 gene encoding atypical Rho family guanine-nucleotide exchange factor (GEF) reported positive role Dock7, target GTPases Rac/Cdc42, downstream c-Jun N-terminal kinase in cell migration (Yamauchi...
Nestin-expressing hair-follicle-associated pluripotent (HAP) stem cells are located in the bulge area of follicle. Previous studies have shown that HAP can differentiate to neurons, glia, keratinocytes, smooth muscle cells, and melanocytes vitro. effected nerve spinal cord regeneration mouse models. Recently, we demonstrated differentiated beating cardiac cells. The differentiation potential was greatest upper part beat rate stimulated by isoproterenol. In present study, observed...
Abstract We previously showed that the stem cell marker nestin is expressed in hair follicle cells which suggested their pluripotency. subsequently nestin‐expressing hair‐follicle pluripotent (hfPS) can differentiate culture to neurons, glial cells, keratinocytes, and other types promote regeneration of peripheral nerve spinal cord injuries upon injection injured or cord. The location hfPS has been termed area (hfPSCA). Previously, were cultured for 1–2 months before transplantation would...
Erythropoietin production has been reported to occur in the peritubular interstitial fibroblasts kidney. Since erythropoietin nephron is controversial, we reevaluated We examined mRNA expressions of and HIF PHD2 using high-sensitive situ hybridization system (ISH) protein expression immunohistochemistry further investigated mechanism by hypoxia vitro human liver hepatocell (HepG2) rat intercalated cell line (IN-IC cells). ISH mice showed proximal convoluted tubules (PCTs), distal (DCTs)...
The effects of hypotonicity on K currents were examined in the single cells isolated from cultured rabbit kidney proximal tubule cells. Using whole cell clamp technique [pipette-filling solution was 145 mM KCl with 0 Ca plus 0.08 ethylene glycol-bis(beta-aminoethylether)-N,N,N',N'-tetraacetic acid], we found that increased 0.8 to 43.5 +/- 12.5 pA at a holding potential (Vp) = mV response reduction extracellular osmolality 290 218 mosmol/kgH2O (n 8). Removal bath reduced osmotic activation by...
Although animal cells swell in hypotonic medium, their volume is subsequently regulated by a net loss of KCl via Ca2(+)-dependent channels. A rise intracellular free calcium ([Ca2+]i) thus appears to be an initial event the adaptation external tonicity, although details this mechanism are not known. To investigate cell regulation, we measured [Ca2+]i (by use fura-2) and diameters single cultured renal proximal convoluted tubule. We found that rapid occurred after were exposed solution (250...
ATP-sensitive K + (K ATP ) channel subunits on the subcellular structures of rat cardiomyocytes were studied with antibodies against Kir6.1 and Kir6.2. According to results Western blot analysis, was strongly expressed in mitochondrial microsome fractions, faintly cell membrane fraction, whereas Kir6.2 mainly fraction weakly fractions. Immunohistochemistry showed that endocardium, atrial ventricular myocardium, vascular smooth muscles. Immunoelectron microscopy revealed immunoreactivity...