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H Ueda

Publications and source records attributed to H Ueda.

At least 37 records · Page 2Linked to original sources
PubMed1999

Selective coupling of mouse brain metabotropic sigma receptor with recombinant Gi1.

Various sigma (sigma) ligands including (+)-pentazocine stimulated [35S]GTPgammaS binding in synaptic membranes from the mouse cerebellum. The (+)-pentazocine-stimulated [35S]GTPgammaS binding was blocked by the treatment of membranes with pertussis toxin (PTX), but completely recovered by the reconstitution of PTX-treated membranes with recombinant Gi1, but not with GoA. These findings suggest that metabotropic sigma receptors are selectively coupled to Gi1 protein.

Animals↗
PubMed1999

Low dose of kyotorphin (tyrosine-arginine) induces nociceptive responses through a substance P release from nociceptor endings.

The intraplantar injection of kyotorphin (Kyo) elicited nociceptive flexor responses in mice in a dose-dependent manner between 0.1 and 100 fmol. These actions were completely blocked by substance P (NK1) receptor antagonists, such as CP-96345 and CP-99994, but not by their inactive derivatives, CP-96344 or CP-100263, nor by MEN-10376, an NK2 antagonist. Kyo-responses were also abolished by the local pretreatment with capsaicin to deplete substance P from nociceptor endings, and in tachykinin 1 gene K/O mice. These findings suggest that Kyo indirectly stimulates nociceptor endings through a local substance P release.

Animals↗
PubMed1999

Activation of Gi1 by lysophosphatidic acid receptor without ligand in the baculovirus expression system.

Lysophosphatidic acid (LPA) receptor has been attracting many neuroscientists' concerns, since it was reported to have a potential role in the neurogenesis, which occurs in the ventricular zone of the developing and adult brain. In the present experiments using baculovirus expression system, the LPA receptor encoded by ventricular zone gene 1 (Edg-2/Vzg-1) was found to be functionally coupled to Gi1, Goa, and G11, but not to GS. The coexpression of LPA receptor markedly decreased the expression of G protein alphai1 or alphaoa subunit, while the basal [35S]GTPgammaS binding significantly increased in the Gi1-preparation. The Scatchard Plot analysis indicates that the expression of LPA-receptor (Edg-2/Vzg-1) showed stimulation of Gi1 without agonist. These results suggest the Edg-2/Vzg-1 has an intrinsic acctivity on Gi1.

Animals↗
PubMed1999

Differential involvement of mu-opioid receptor subtypes in endomorphin-1- and -2-induced antinociception.

We investigated the role of mu-opioid receptor subtypes in both endomorphin-1 and endomorphin-2 induced antinociception in mice using supraspinally mediated behavior. With tail pressure as a mechanical noxious stimulus, both intracerebroventricularly (i.c.v.) and intrathecally (i.t.) injected-endomorphins produced potent and significant antinociceptive activity. Antinociception induced by i.t. and i.c.v. injection of endomorphin-1 was not reversed by pretreatment with a selective mu1-opioid receptor antagonist, naloxonazine (35 mg/kg, s.c.). By contrast, antinociception induced by i.t. and i.c.v. endomorphin-2 was significantly decreased by mu1-opioid receptor antagonist. Antinociception of both i.t. and i.c.v. endomorphin-1 and -2 was completely reversed by pretreatment with beta-funaltrexamine (40 mg/kg, s.c.). The results indicate that endomorphins may produce antinociception through the distinct mu1 and mu2 subtypes of mu-opioid receptor.

Analgesics, Opioid↗
PubMed1999

Peripheral morphine analgesia resistant to tolerance in chronic morphine-treated mice.

Intraplantarly (i.pl.)-injected morphine showed a peripheral analgesia in experiments to assess the blockade of bradykinin (i.pl.)-induced nociceptive flexor response in mice. The peripheral morphine analgesia in mice which developed central analgesic tolerance to chronic morphine (10 mg/kg s.c., 5 days), was equivalent to that in vehicle-treated mice in any doses between 0.1 and 1 nmol (i.pl.). These findings suggest that morphine tolerance in the central analgesia may use unique mechanisms deficient in the peripheral nervous system.

Analgesics, Opioid↗
PubMed1999

Phosphorylation of F-actin-associating G protein gamma12 subunit enhances fibroblast motility.

Eleven isoforms of G protein gamma subunit have been found thus far, but the precise roles of individual gamma subunits are not known. The gamma12 subunit has two unique properties: phosphorylation by protein kinase C and association with F-actin. To elucidate the role of gamma12, we overexpressed gamma12 and other gamma subunits in NIH 3T3 cells together with the beta1 subunit. The overexpressed gamma12 as well as endogenous gamma12, but not gamma2, gamma5, and gamma7 subunits, associated with cytoskeletal components. Expression of gamma12 induced remarkable changes including cell rounding, disruption of stress fibers, and enhancement of cell migration, but expression of other gamma subunits did not induce significant changes. Deletion of the N-terminal region of gamma12 decreased the abilities of gamma12 to associate with cytoskeletal fractions, to induce cell rounding, and to increase cell motility. Replacement by alanine of Ser2 of gamma12 (Ser1 of a mature gamma12 protein), a phosphorylation site for protein kinase C, eliminated these effects of gamma12, whereas a mutant in which Ser2 was replaced with glutamic acid showed effects equivalent to wild-type gamma12. These results indicate that phosphorylation of gamma12 at Ser2 enhances the motility of cells.

3T3 Cells↗
PubMed1999

Open sandwich ELISA with V(H)-/V(L)-alkaline phosphatase fusion proteins.

The Sandwich ELISA is a widely used technique to measure antigen concentration. Recently, a novel ELISA based on the interchain interaction of separated V(H) and V(L) chains from a single antibody variable region (Fv) was proposed (Open Sandwich ELISA). Since it employs a single antibody recognizing one epitope, the assay requires, in essence, only one cycle of incubation and washing steps. To demonstrate this directly, we have constructed a recombinant gene fusion encoding the V(H) chain of an anti-hen egg lysozyme (HEL) antibody HyHEL-10 and Escherichia coli alkaline phosphatase (V(H)-PhoA). The same type of gene fusion using V(L) chain instead of V(H) chain (V(L)-PhoA) was also constructed and the proteins were obtained with an E. coli expression/secretion system. Open Sandwich ELISAs were performed using microtiter plates with immobilized V(L) or V(H) fragment, and V(H)-PhoA or V(L)-PhoA, respectively, as the detection reagent which was simultaneously added to each well with samples. As a result, HEL concentrations in the samples were determined after one round of incubation and washing steps, with a signal generated in a direct relationship to the concentration of HEL added to the reaction mixture. The minimum detectable HEL concentration was approximately 10 ng/ml, which was almost equal to the value previously obtained with plate-immobilized V(L) and V(H) fragment displayed on M13 phage. When the active-site mutant V(H)-PhoA(D101S) was employed instead of V(H)-PhoA and reacted at an optimum pH of 10, a significant enhancement in signal was attained.

Alkaline Phosphatase↗
PubMed1999

Interaction of a lectin from Psathyrella velutina mushroom with N-acetylneuraminic acid.

A lectin from the fruiting body of Psathyrella velutina has been used as a specific probe for non-reducing terminal N-acetylglucosamine residues. We reveal in this report that P. velutina lectin recognizes a non-reducing terminal N-acetylneuraminic acid residue in glycoproteins and oligosaccharides. Binding of biotinyl P. velutina lectin to N-acetylneuraminic acid residues was prevented by desialylation of glycoconjugates and was distinguished from the binding to N-acetylglucosamine. Sialooligosaccharides were retarded or bound and eluted with N-acetylglucosamine on a P. velutina lectin column, being differentiated from each other and also from the oligosaccharides with non-reducing terminal N-acetylglucosamine which bound more strongly to the column.

Basidiomycota↗
PubMed1999

Decreased expression of myotonic dystrophy protein kinase and disorganization of sarcoplasmic reticulum in skeletal muscle of myotonic dystrophy.

Pathological expression of myotonic'dystrophy protein kinase (DMPK) in skeletal muscle of myotonic dystrophy (DM) was studied by Western blot analysis, immunohistochemistry, and immunoelectron microscopy of DMPK. Western blot analysis showed that DMPK protein in DM skeletal muscles dramatically decreased. DMPK-positive muscle fibers showed typical DM pathological changes such as type I atrophy, central nuclei, nuclear chains, and sarcoplasmic masses. In degenerated DMPK-positive muscle fibers, cross-striated bands disappeared, and irregular granular DMPK-positive materials appeared in sarcoplasm. By immunoelectron microscopy, DMPK was localized in the terminal cisternae of the sarcoplasmic reticulum (SR) in DM muscle. Swollen DMPK-positive SRs were detected between well preserved myofibrils in the early stage of DM muscle degeneration, and degenerated intramembranous structures with DMPK and an accumulation of mitochondria were observed between disorganized myofibrils in degenerated DM muscle. We concluded that SR is the primary site of the degeneration of DM skeletal muscle and that the decreased DMPK might cause dysregulation of intracellular calcium metabolism, which is followed by DM muscle degeneration.

Adenosine Triphosphatases↗
PubMed1999

Seasonal changes in expression of neurohypophysial hormone genes in the preoptic nucleus of immature female masu salmon.

In relevance to osmoregulatory and reproductive functions, activity of the hypothalamic magnocellular neurosecretory system may vary seasonally in teleosts. The changes in the expression of vasotocin (VT) and isotocin (IT) genes were thus studied by an in situ hybridization technique and an immunohistochemical avidin-biotin complex method in immature female masu salmon (Oncorhynchus masou). The plasma levels of testosterone and estradiol were also measured by enzyme immunoassay. Fish were sampled in March, May, August, and November 1994 and January 1995. The intensity of autoradiographic hybridization signals and immunoreactivity were determined in individual neurosecretory cells (NSC) in the rostroventral, middle, and dorsocaudal regions of the magnocellular part of the preoptic nucleus (PM). The VT hybridization signals and immunoreactivity were high in November, along with the elevation of plasma levels of testosterone and estradiol. These results suggest that sex steroid hormones are involved in seasonal regulation of VT gene expression. The hybridization signals for IT mRNA were increased in May and decreased in November, whereas IT immunoreactivity was low in March and high in November. NSCs thus showed seasonal variations in the intensity of hybridization signals for VT and IT mRNAs and immunoreactivity of VT and IT, although the patterns of changes were different between VT and IT. VT and IT genes may be seasonally expressed under different regulatory mechanisms.

Animals↗
PubMed1999

Differences in seasonal expression of neurohypophysial hormone genes in ordinary and precocious male masu salmon.

Our previous study showed the seasonal variations in expression of vasotocin (VT) and isotocin (IT) genes in preoptic magnocellular neurons of female masu salmon (Oncorhynchus masou). The changes in the level of VT mRNA were coincident with those in plasma testosterone and estradiol levels. In the present study, generality of this phenomenon in salmonid was verified in males. We examined changes in expression of VT and IT genes by an in situ hybridization technique and an immunohistochemical avidin-biotin complex method in the preoptic nuclei of ordinary and precocious male masu salmon. Plasma levels of testosterone and estradiol were measured by enzyme immunoassay. Fish were sampled in March, May, August, and November 1994 and January 1995. The intensities of hybridization signals for VT and IT mRNAs, as well as immunoreactivity of VT and IT, showed seasonal variations, although the profiles were different between the ordinary and precocious males. In the ordinary males, the intensities of hybridization signals for VT and IT mRNAs were high in January. These strong hybridization signals, representing elevation of VT and IT gene expression, were accompanied by increases in plasma levels of testosterone and estradiol. However, in precocious males, changes in VT and IT mRNA levels were not coincident with variation of plasma levels of sex steroid hormones. The sensitivity to sex steroid hormones of VT and IT gene expression may be different between the ordinary and precocious male masu salmon.

Animals↗
PubMed1999

Video-assisted thoracoscopic esophagomyotomy for achalasia after pulmonary lobectomy.

A 52-year-old man developed achalasia and a lung abscess due to aspiration pneumonia. We conducted a right upper lobectomy by thoracotomy for the abscess and, 2 weeks later, video-assisted thoracoscopic myotomy and fundoplication (modified Belsey Mark IV procedure) though the left thorax for achalasia. Three months after surgery, the patient was free of dysphasia and chest pain and had regained his original weight. Esophageal myotomy and fundoplication using video-assisted thoracoscopy appear to be feasible in treating achalasia involving impaired pulmonary function.

Endoscopy↗
PubMed1999

"In vivo cryotechnique" in combination with replica immunoelectron microscopy for caveolin in smooth muscle cells.

A novel "in vivo cryotechnique" with replica immunoelectron microscopy was developed for detecting caveolin localization on replica membranes prepared directly from living smooth muscle cells. After quick-freezing mouse duodenal walls by our "in vivo cryotechnique", the specimens were prepared for freeze-fracture and deep-etch replica membranes. Then they were treated with 5% SDS and 0.5% collagenase to keep some antigens on the replica membranes. The immunogold method could be used to clarify the localization of the caveolin antigen in relation to three-dimensional ultrastructures of living smooth muscle cells. Our new cryotechnique can provide native organization of functional molecules in living cells.

Animals↗
PubMed1999

Mechanisms underlying the age-related decrement in the human sweating response.

To examine the mechanisms underlying the age-related decrement in the ability to sweat, seven older (64-76 years) and seven younger (20-24 years) men participated in a 60-min sweating test. The test consisted of placing the subject's lower legs in a water bath at 42 degrees C while sitting in a controlled environment of 35 degrees C ambient temperature and 45% relative humidity. The rectal (Trc) and skin temperatures, local sweating rates (m(sw): on the forehead, chest, back, forearm and thigh) and the frequency of sweat expulsion (f(sw)) were measured during the test. No group difference was observed in the mean body temperature (Tb) throughout the passive heating, although the older men had a higher Tre and a lower mean skin temperature during the last half of the 60-min test. There were no group differences in the Tb threshold for sweating, although the time to the onset of sweating tended to be longer for the older men regardless of body site. The m(sw) increased gradually for approximately 35 min after the start of heat exposure in the older men and for 30 min in the younger men and then reached a steady state. During the first half of the test, the older men had a significantly lower m(sw) at all sites. During the last half of the test, only m(sw) on the thigh was significantly lower in the older men than in the younger men. There was no group difference in the slope of f(sw) versus Tb (an indicator of the change in the central sudomotor response to thermal input). The slope of m(sw) versus f(sw) (an indicator of the change in peripheral activity in response to central sudomotor changes) was significantly lower on the thigh in the older men, but there were no differences for the other sites. These results suggest that in older men the lower thigh m(sw) observed during the last half of the heat test was possibly due to age-related modifications of peripheral mechanisms involving the sweat glands and surrounding tissues. It was not due to a change in the central drive to sudomotor function. Furthermore, the sluggish m(sw) responses in the older men appear to have been related to age-related modifications of the sensitivity of thermoreceptors in various body regions to thermal stimuli. They may also involve lower sweat glands' sensitivity to cholinergic stimulus or sluggish vasodilatation, and do not reflect age-related changes in the central drive.

Adult↗
PubMed1999

Gene transfection of hepatocyte growth factor attenuates reperfusion injury in the heart.

BACKGROUND: Hepatocyte growth factor (HGF), a ligand for the c-Met receptor tyrosine kinase, plays a role as organotrophic factor for regeneration of various organs. HGF has an angiogenic activity and exhibits a potent antiapoptotic activity in several types of cells. Although HGF and the c-Met/HGF receptor are expressed in the heart, the role of HGF in the heart has remained unknown. METHODS: After we analyzed changes in expression of endogenous HGF and c-Met mRNA levels in the rat left ventricle after myocardial infarction, the human HGF gene in hemagglutinating virus of Japan (HVJ)-liposome was transfected into the normal whole rat heart. Three days after transfection, the heart was subjected to global warm ischemia and subsequent reperfusion, followed by assessment of its cardiac functions. RESULTS: Both HGF and c-Met/HGF receptor mRNAs were expressed in adult rat heart, and c-Met/HGF receptor mRNA was upregulated in response to myocardial infarction. HGF-transfected heart showed significant increase of human HGF protein level in the heart. Cardiac functions in terms of the left ventricular developed pressure, maximum dp/dt, and pressure rate product in hearts with HGF gene transfection were significantly superior to those in control hearts. In addition, leakage of creatine phosphokinase in the coronary artery effluent in hearts with HGF gene transfection was significantly lower than that in control hearts. CONCLUSIONS: These data indicated that both HGF and c-Met/HGF receptor mRNAs were upregulated in response to myocardial ischemic injury, and that HGF is likely to have a cytoprotective effect on cardiac tissue, presumably through the c-Met/HGF receptor.

Animals↗
PubMed1999

Gene transfection of beta 2-adrenergic receptor into the normal rat heart enhances cardiac response to beta-adrenergic agonist.

BACKGROUND: Beta-adrenergic receptor system has a major role in cardiac contraction. If the receptor can be increased by gene transfection by means of intracoronary infusion of beta 2-adrenergic receptor to the hearts in which the receptor is down-regulated, this maneuver may improve the cardiac function and may be applied as one therapeutic approach during cardiopulmonary bypass or percutaneous cardiopulmonary support. METHODS AND RESULTS: The beta 2-adrenergic receptor complementary DNA was transfected in vivo to the normal rat heart by intracoronary infusion by means of a hemagglutinating virus of Japan liposome method, and the transfected heart was transplanted into the abdomen of another rat. Four days after transfection, the sarcolemma of the cardiomyocytes was well labeled by immunohistochemical labeling. Expression of beta-adrenergic receptor in the heart was approximately 4 times greater than that in control hearts (134 +/- 42 vs 33 +/- 4 fmol/mg protein) according to a ligand binding assay. The cardiac response of the transfected heart to isoproterenol was shown to be enhanced in a Langendorff perfusion system: after isoproterenol, developed pressure and maximal derivative of the left ventricle were greater than in the control heart (200 +/- 12 vs 174 +/- 6 mm Hg and 4110 +/- 130 vs 3491 +/- 255 mm Hg/sec), and the minimal derivative of the left ventricle was markedly smaller (-3040 +/- 267 vs -2528 +/- 131 mm Hg/sec). CONCLUSIONS: These results indicate that expression of beta 2-adrenergic receptor was approximately 4 times greater than in normal rat hearts by gene transfection using a hemagglutinating virus of Japan liposome method, and the transfected hearts demonstrated marked enhancements in cardiac response to beta-agonist, suggesting that transfer of this gene by intracoronary infusion has potential as a novel approach to enhance cardiac function.

Adrenergic beta-Agonists↗
PubMed1999

Intrathoracic esophageal replacement in the dog with the use of an artificial esophagus composed of a collagen sponge with a double-layered silicone tube.

OBJECTIVES: Intrathoracic esophageal replacement with an artificial esophagus is considered difficult. We attempted to replace the intrathoracic esophagus with an artificial esophagus composed of a collagen sponge with a double-layered silicone tube and examined the state of host tissue regeneration. METHODS: A 5-cm long gap was created in the intrathoracic esophagus in 9 dogs and repaired by interposition of our prosthesis. The dogs were fed only by intravenous hyperalimentation for 28 days. The silicone tube was removed at 29 days after the operation, and oral feeding was reintroduced. RESULTS: One dog was put to death at each of the following times: 1, 2, 3, 3, 6, 12, and 24 months after the operation. One dog is still surviving without problems after more than 26 months. One dog died of malnutrition at 10 months. In all dogs, the host regenerated tissue had replaced the resulting gap at the time of silicone tube removal. The mucosa had fully regenerated within 3 months and the glands within 12 months. The process of stenosis and shrinkage was complete within 3 months and did not advance thereafter. The lamina muscularis mucosae were observed as islets of smooth muscle within 12 months. Although the skeletal muscle regenerated close to the anastomoses, it did not extend to the middle of the regenerated esophagus even after 24 months. CONCLUSIONS: Use of a collagen sponge with a double-layered silicone tube was shown to be feasible even in the thorax and to allow the regenerated host tissue, consisting of the mucosa, glands, and lamina muscularis mucosae, to replace the esophageal gap.

Anastomosis, Surgical↗