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T Tsujino

Publications and source records attributed to T Tsujino.

At least 19 recordsLinked to original sources
PubMed1994

Alpha-, beta II- and gamma-subspecies of protein kinase C localized in the monkey hippocampus: pre- and post-synaptic localization of gamma-subspecies.

Protein kinase C (PKC) has attracted wide attention as a key enzyme for the expression of long-term potentiation in the hippocampus, a basic model for memory. It is of interest to study the detailed localization of PKC subspecies in the monkey hippocampus. We used immunocytochemistry to examine the localization of PKC subspecies in the hippocampus of the monkey, Macaca mulatta. Subspecies of PKC in the monkey could be separated by hydroxyapatite chromatography and the elution profile proved to be similar to that of the rat. Antibodies against each alpha, beta II and gamma-subspecies of the rat specifically reacted with the respective subspecies of monkey PKC. The alpha-, beta II- and gamma-subspecies were distinctly distributed in the hippocampus. The beta I-subspecies was not evident in the hippocampus. While both the alpha- and gamma-subspecies immunoreactive pyramidal cells were distributed throughout the hippocampus (CA1-CA3), the beta II-subspecies immunoreactive cells were scattered only in the CA1 region. The gamma-subspecies was found in granule cells and dendrites in the dentate gyrus, in mossy fibers and in their terminals in the CA3 region. The alpha-subspecies was also present in granule cells and in the dendrites but not in the mossy fibers. Glial cells did not stain with any of the antibodies used. Electron microscopy clearly showed that the gamma-subspecies was localized in both presynaptic terminals and post-synaptic dendrites. These observations suggest that subspecies of PKC in the monkey hippocampus may be involved in distinct functions and that the gamma-subspecies of PKC may act pre- and post-synaptically in pyramidal cells of the hippocampus.

Amino Acid Sequence↗
PubMed1994

Calcium supplementation inhibits the expression of parathyroid hypertensive factor in DOCA-salt hypertensive rats.

To elucidate the antihypertensive mechanism of oral calcium supplementation in salt-dependent hypertension, we investigated the hypertensive activity of plasma from DOCA-salt hypertensive rats fed with (DS-Ca) or without (DS) a high calcium diet. Four weeks of calcium supplementation (4% CaCl2) attenuated the blood pressure increase in DS rats. Intravenous bolus injection of dialyzed plasma (1.0-kDa cutoff) from DS rats to normotensive rats resulted in a sustained elevation in blood pressure, whereas that from DS-Ca rats did not. As the endothelin concentration was not different between the two groups, the circulating hypertensive substance in DS rats may be identical to parathyroid hypertensive factor (PHF) and the inhibition of its expression by calcium may be involved in the hypotensive mechanism of high calcium diets in salt-dependent hypertension.

Animals↗
PubMed1994

[New method of retrograde urethrography. Clinical study of autourethrography].

Autourethrography (A-UG), a new method of retrograde urethrography was developed, in which the patient injects the contrast medium by himself under fluoroscopical observation by urologists out side of the room. For clinical study of A-UG, comparative study between A-UG and the conventional retrograde urethrography (C-UG) was performed on 20 patients with benign prostatic hypertrophy. The mean age was 68.8 years (range 49-85 years) in A-UG and 69.4 years (range 61-86 years) in C-UG. We evaluated complications of A-UG, compared with these of C-UG. Opacification of the posterior urethra was achieved in all but one in A-UG. None of these patients in A-UG experienced pain during the examination of A-UG. On the other hand, all patient experienced pain in C-UG. Urethral bleeding occurred in only one of 19 patients in A-UG, compared with eighteen of 20 patients in C-UG. Extravasation occurred in one of 19 patients in A-UG, compared with three patients of 20 patients in C-UG. A-UG left the urologists free from the radiological exposure. It is concluded that A-UG is highly useful examination for patients and urologists.

Aged↗
PubMed1994

Selective alpha 1-adrenergic inhibition improves decrease glucose disposal in patients with essential hypertension.

This study evaluated insulin secretion and insulin sensitivity before and after short-term oral administration of doxazosin in patients with essential hypertension. The hypertensive group consisted of 11 nonobese subjects (aged 41.0 +/- 2.5 years (mean +/- SEM), body mass index 24.0 +/- 0.53 kg/m2). The normotensive group consisted of 12 subjects matched to the hypertensive group for age and body mass index. The hypertensive group showed significantly higher concentrations of prestimulated and stimulated plasma insulin and plasma C peptide than normal groups. The insulin-mediated glucose disposal rate during euglycaemic clamp (M-value) was significantly lower in the hypertensive group than in normal controls (7.32 +/- 0.56 vs 8.88 +/- 0.34 mg/kg/min, P < 0.05). After one month of doxazosin treatment blood pressure was significantly reduced (P < 0.05). The short-term administration of doxazosin improved the M-value significantly to 8.60 +/- 0.62 mg/kg/min without a significant change in stimulated plasma C-peptide level. These data show that hypertension is associated with increased insulin secretion and impaired insulin sensitivity. Selective alpha 1-adrenergic inhibition with doxazosin improves the decreased glucose disposal rate associated with hypertension.

Administration, Oral↗
PubMed1993

Immunocytochemical localization of alpha-, beta I-, beta II- and gamma-subspecies of protein kinase C in the motor and premotor cortices of the rhesus monkey.

We obtained evidence for the localization of alpha-, beta I-, beta II- and gamma-subspecies of protein kinase C (PKC) in the monkey motor and premotor cortices (Brodmann's areas 4 and 6). In Brodmann's area 4, the immunoreactivity for the alpha-PKC was present in horizontal and round cells in the layers I and II, and small pyramidal cells in layer III and also in the glial cells in subcortical white matter. The alpha-PKC immunopositive glial cells contained GFAP-immunoreactive product. The beta I-PKC immunoreactivity was present in the round cells in layer I and in the pyramidal cells in the layer V, including Betz cells. The beta II-PKC immunoreactivity was observed as small dots in perikarya of the small and medium-sized pyramidal cells in layers II, III, V and VI, but not in layer I. The gamma-PKC immunoreactive cell bodies were observed in layers II, III and VI, and most of the immunoreactive cells were pyramidal. Intense gamma-PKC immunoreactivity was found in the neuropils of layers I and II. Similar distributions of four PKC subspecies were seen in Brodmann's area 6, except that beta I-PKC immunoreactive Betz cells were not present. The unique localization of PKC subspecies suggested that each PKC subspecies was involved in the specific function in motor and premotor cortices of the rhesus monkey.

Animals↗
PubMed1993

Molecular structure and transcriptional function of the rat vascular AT1a angiotensin receptor gene.

Rat vascular angiotensin receptors (AT1a receptors) are encoded by two mRNA transcripts sharing an identical receptor coding sequence but differing in their 5' and 3' untranslated sequences. We screened male Sprague-Dawley rat genomic libraries to clone the vascular AT1a receptor gene. Two sets of overlapping clones were isolated that encode over 90 kb of genomic sequence around the AT1a receptor gene. Four overlapping clones were identified from the 5' flanking portion of the gene. These contain the promoter region and two exons, 141 bp and 89 bp in size, respectively, encoding the alternatively spliced 5' untranslated mRNA sequence. Six additional clones overlap each other but do not overlap the set of clones from the 5' flanking region of the gene. These contain a single 1977-bp exon that encodes 900 bp of the 5' and 3' untranslated sequences in addition to a 1077-bp open reading frame identical to that found in vascular smooth muscle cell AT1a receptor cDNAs. Primer extension and RNase protection studies indicate that the transcription start site for this gene begins 9 bp upstream from the most 5' sequence found within the AT1a receptor cDNAs. Our mapping studies of the cloned gene, which so far includes an uncloned gap within the second intron, indicate that the transcription start site is no less than 67 kb upstream from the receptor coding exon. Promoter-reporter assays were performed by transfection of vascular smooth muscle cells with deletions of a 3.2-kb promoter region fused to a luciferase cDNA reporter plasmid. Relatively strong basal transcriptional activity is observed from the 5'-most 2 kb of the promoter and diminishes markedly with deletions within 1 kb of the early promoter region, suggesting strong promoter elements in the more upstream regions of the gene. Deletion of a 53-bp early promoter region containing the transcription start site and a putative TATA box completely abolishes the ability of upstream elements to drive transcription of the luciferase cDNA. These results indicate that we have isolated the AT1a receptor gene and its functional promoter.

Animals↗
PubMed1993

[Calcification of vas deferens diagnosed by transrectal ultrasonography].

A 30-year-old male patient without diabetes mellitus and tuberculosis was referred to our outpatient department for the purpose of further examinations of azoospermia. Transrectal ultrasonography revealed the bilateral calcifications of vas deferens. Kidney-ureter-bladder X-ray and computerized tomography revealed also the same findings. Seminal vesiculography revealed no obstructive sign of vas deferens. Histopathology of testes showed hypoplasia. Judging from these findings, we diagnosed the case as calcification of vas deferens associated with spermatogenic disturbance. Review of the 31 cases reported in the Japanese literature including our case was performed.

Adult↗
PubMed1993

[Assay of erythropoietin in serum with short term enzyme linked immunosorbent assay method--the clinical significance, Part 1: Relation to anemia in renal failure and hematological disorders].

With a newly developed enzyme linked immunosorbent assay kit TOYOBO Co. in which 2 anti-EPO monoclonal antibodies were used, we assayed EPO concentration in sera from normal adults, 168 patients with renal failure and 333 patients with hematological disorders. In the patients with renal failure, serum EPO level was normal (52.9%) or reduced (42.9%), and there was no correlation to their hematocrits. However, there was an increment in EPO concentration correlated to their severity of anemia in the most patients with hematological disorders, such as iron deficiency anemia (correlation coefficient r = -0.74), aplastic anemia (r = -0.89), leukemia (r = -0.81), and MDS (r = -0.65). On the other hand, EPO concentration in sera from all the untreated patients with polycythemia vera were significantly low level. But the concentrations of EPO from the patients successfully treated, with normal hematocrit were recovered to normal level. In the patients with secondary polycythemia, there were much varieties in EPO level. Assay of EPO in blood is important not only for diagnosis of polycythemia but also for the analysis of anemia and clinical use of EPO in vivo. The method described here is accurate and technically not complicated, and could be widely induced in most laboratories.

Adolescent↗
PubMed1993

[Assay of erythropoietin in serum with short term enzyme linked immunosorbent assay method--the clinical significance: Part 2--:Relation to serum iron, UIBC and ferritin in renal failure and hematological disorders].

With a newly developed short term enzyme linked immunosorbent assay kit (TOYOBO Co.), in which 2 kinds of anti-EPO monoclonal antibodies were used, we assayed EPO concentration in sera from patients with renal failure and hematological disorders. In this report, the EPO data were analysed in relation to serum iron concentrations, with ferritin and UIBC. In the patients with renal failure, there was no significant correlation between EPO concentration and serum iron, ferritin, nor UIBC concentration. On the other hand, in the patients with hematological disorders, there were two types. One was in patients with iron deficiency anemia, whose serum EPO was negatively correlated to serum iron (r = -0.64) and ferritin (r = -0.59), but positively related to UIBC (r = 0.27). The another was the pattern in patients with aplastic anemia, leukemia and MDS, whose serum EPO positively correlated to iron and ferritin but negatively correlated to UIBC. In the patients with aplastic anemia serum EPO had good correlation to serum iron (r = 0.62), ferritin (r = 0.60) and UIBC (r = -0.46). The relationship of EPO to iron in the patients with leukemia (r = 0.54), and EPO to ferritin in the patients with MDS (r = 0.42) show significantly positive correlation coefficient.(ABSTRACT TRUNCATED AT 250 WORDS)

Enzyme-Linked Immunosorbent Assay↗
PubMed1992

Expression of Fos-like immunoreactivity by yohimbine and clonidine in the rat brain.

To elucidate the role of alpha 2-adrenoceptors in transcriptional control in the rat brain, we localized the Fos-like immunoreactivity (Fos-LI) induced by alpha 2-adrenoceptor agonists and by an antagonist. Injections of yohimbine (5 mg/kg, i.p.) into rats led to the induction of Fos-LI in areas with a dense alpha 2-adrenoceptor binding such as the locus coeruleus, the bed nucleus of stria terminalis, the central nucleus of amygdaloid complex, the paraventricular nucleus, the nucleus tractus solitarius, and ventrolateral medulla oblongata. Clonidine (500 micrograms/kg, i.p.) suppressed the Fos expression by yohimbine in these nuclei, and clonidine (100 micrograms/kg, i.p.) or guanabenz (4 mg/kg, i.p.) induced Fos-LI in oxytocin neurons in the paraventricular and supraoptic nuclei in the hypothalamus. Thus, the alpha 2-adrenoceptor is involved in transcriptional control via Fos expression in neurons related to autonomic and other functions.

Animals↗
PubMed1992

Tyrosine kinase activity of epidermal growth factor receptor in human gastric carcinomas.

We examined tyrosine kinase activity of epidermal growth factor (EGF) receptor in a total of 34 human gastric carcinomas as well as in non-neoplastic gastric mucosa from the same patients. EGF receptor kinase activity of the carcinoma tissues and the non-neoplastic mucosa were 1.28 +/- 1.00 (Mean +/- S.E.) and 0.16 +/- 0.04 respectively, if the EGF receptor kinase activity of human placenta is 10. Twenty-one (62%) carcinoma tissues showed higher EGF receptor kinase activity than corresponding non-neoplastic mucosa, while in 6 cases (18%) the kinase activity was higher in the non-neoplastic mucosa than in the tumor tissues. No obvious correlation was observed between the increased kinase activity in the tumors and histological type or tumor staging. One tumor showed extremely high receptor kinase activity with ERBB gene amplification. This tumor showed strong immunoreactivity to EGF itself.

ErbB Receptors↗
PubMed1992

Effect of ciclosporin on cardiac output and regional blood flow in rats: ciclosporin-induced nephropathy and its prevention with calcium channel blocker.

The effect of ciclosporin (CS) on cardiac output (CO) and regional blood flow was studied using the microsphere method in heminephrectomized rats with and without renal arterial clamping prior to the administration of CS. The effect of a calcium (Ca) channel blocker, verapamil, was also examined on CS-induced nephropathy. CS at a dose of 40 mg/kg per day was given orally using a gastric tube for 7 days. Verapamil was given in the drinking water for 7 days. Significant increases in blood urea nitrogen (BUN) and serum creatinine (sCr) with a significant decrease in renal inulin clearance (CIn) were noted after 7 days of CS administration in both intact and ischemic-kidney groups, indicating the development of CS-induced nephropathy. The ischemic-kidney group showed a significantly severe nephropathy as compared with the intact-kidney group. As for change in CO and regional blood flow, CS caused a significant decrease in CO, renal blood flow (RBF) and brain blood flow, while hepatic arterial blood flow and muscular blood flow significantly increased. The renal outer cortical blood flow decreased markedly while the inner cortical blood flow remained unchanged. Although verapamil slightly but significantly decreased mean arterial blood pressure in CS-treated rats, CO and its distribution did not change. BUN and sCr were not significantly ameliorated in the intact-kidney group. However, in the ischemic-kidney group, verapamil caused a significant improvement in RBF, ameliorating CS-induced elevation of BUN and sCr, and a decrease in CIn.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

Frequent loss of heterozygosity on chromosomes 1q, 5q, and 17p in human gastric carcinomas.

Recently, loss or inactivation of genes at specific chromosomal loci has been considered to be one of the important mechanisms during the development of human tumors. In order to identify tumor suppressor genes for gastric carcinoma, we performed restriction fragment length polymorphism analysis on 48 human gastric carcinomas. Allele losses were investigated for 14 specific loci on chromosomes 1, 5, 6, 7, 10, 11, 12, and 17. Loss of heterozygosity on chromosome 17p13.1 (p53 locus) was detected in 13 (68%) of 19 informative cases. Well-differentiated adenocarcinoma showed high frequencies of allele losses on chromosomes 5q (60%) and 17p (67%) in early cancers and on chromosomes 1q (67%), 5q (36%), 7p (33%), 7q (39%), and 17p (73%) in advanced cancers. In poorly differentiated adenocarcinomas, loss of heterozygosity was detected on chromosomes 1p (38%), 12q (31%), and 17p (60%). Allele losses on chromosomes 1q, 5q, and 7p were not detected in poorly differentiated adenocarcinoma, their frequencies being significantly different between the two histological types. These results suggest that allele loss on chromosome 17p is a common event in gastric carcinoma, regardless of histological type, and that allele loss on chromosome 5q may play a role in the carcinogenesis of well-differentiated adenocarcinoma. Additionally, allele losses on chromosomes 1q and 7p may be involved in the progression of well-differentiated adenocarcinoma.

Adenocarcinoma↗
PubMed1991

[Effects of verapamil on cyclosporine. A (CsA)-induced nephropathy in ischemic kidney model in rats: changes in systemic hemodynamics and hepatic and renal microsomal cytochrome P-450].

We have examined the effect of verapamil on CsA-induced nephropathy by measurement of systemic hemodynamics including each organ blood flow using the microsphere method in ischemic kidney model of hemi-nephrectomized Wistar rats. Hepatic and renal microsomal cytochrome P-450 contents and their enzyme activities were measured to study the correlation between CsA-induced nephropathy and induction of hepatic and renal microsomal cytochrome P-450. All rats were hemi-nephrectomized (l-nephrectomy) and were classified into the following 6 groups: 1) control groups, 2) CsA at a dose of 40 mg/kg per day orally for 7 days (CsA group), 3) Oral administration of verapamil for 7 days in the CsA group (CsA + V group), 4) 20 min clamping of the remaining right kidney pedicle (Ischemic, Is group), 5) CsA was administered in the Is group (Is + CsA group), 6) Addition of verapamil to CsA in the Is + CsA group (Is + CsA + V group). Verapamil was given in the drinking water and the average dose calculated from the amount of drinking was 4.7 +/- 1.0 mg/kg per day and 5.2 +/- 0.7 mg/kg per day for the CsA + V group and the Is + CsA + V group, respectively. CsA caused significant increases in BUN and serum creatinine (sCr) with a significant decreases in renal inulin clearance (CIn) in all groups. When compared with the Is group, CsA caused significant decreases in cardiac output and all organ blood flow especially in renal blood flow with significant increases in BUN and sCr in the Is + CsA group.2+ degree of nephropathy.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Expression of ERBB2 in human gastric carcinomas: relationship between p185ERBB2 expression and the gene amplification.

The expression of p185ERBB2 in a total of 34 human gastric carcinoma tissues as well as in corresponding normal mucosa was examined by Western blotting. More than 70% of both tumor tissues and normal mucosa showed p185ERBB2 expression at various levels. Eighteen (55%) cases revealed higher levels of p185ERBB2 in the tumor than in normal mucosa, while 13 (38%) cases showed lower levels in the tumor tissues. Higher expression of p185ERBB2 was frequently observed in well differentiated adenocarcinomas, with the incidence between well differentiated type and poorly differentiated type being significantly different (P less than 0.05). Comparative immunohistochemical analysis revealed the consistent results with p185ERBB2 expression obtained by Western blotting in well differentiated adenocarcinomas. Of the 34 cases, three well differentiated adenocarcinomas had extremely high levels of p185ERBB2. ERBB2 gene was amplified in two of the three tumors, but the amplification differed by the tumor site from where the sample was obtained. Another tumor which showed an extremely high level of p185ERBB2 but no gene amplification demonstrated a high level of binding protein to the TATA box that is located in the promoter of the ERBB2 gene. A high level of TATA-binding protein was also detected in gastric carcinoma cell lines which contain a single copy of ERBB2 gene and a high expression of p185ERBB2.

Blotting, Northern↗
PubMed1990

Immunocytochemical localization of protein kinase C subspecies in the rat spinal cord: light and electron microscopic study.

Distinct expression of protein kinase C (PKC) subspecies in the central nervous system suggested that each subspecies has a distinct neural function in the processing and modulation of a variety of physiological responses to external signals. In this study, the cellular and subcellular distributions of beta I-, beta II- and gamma-subspecies of PKC were demonstrated by using subspecies-specific antibodies in the rat spinal cord. By light microscopy both gamma- and beta II-subspecies immunoreactivities were found only in neurons of the substantia gelatinosa and axons of the dorsal corticospinal tract in the spinal cord. Use of a double staining method, however, revealed that beta II-subspecies immunoreactivity was localized in the outer part of the lamina II, whereas gamma-subspecies immunoreactivity was found in the inner part of lamina II. Immunoreactive neurons containing beta I-subspecies were scattered in the substantia gelatinosa. Beta I-subspecies immunoreactivity varied in neuronal types. Furthermore, electron microscopic analysis clearly showed the subcellular distribution of these subspecies to be different from one another. Dense gamma-subspecies immunoreactivity was found in the cytoplasm except within cell organelles of the perikarya and dendrites. Some nuclei were stained as strongly as the cytoplasm and others were stained less heavily. The nucleoli had faint or no immunoreactivity. Reaction products of beta II-subspecies were located against the inner plasma membrane but not seen in the nuclei or nucleoli. Beta I-subspecies immunoreactivity appeared to be associated with the Golgi complex. No immunoreactive products of any PKC subspecies were detected in the presynaptic terminals. The different patterns of expression described above imply that individual PKC subspecies may have a specific function in modulating the neuronal activity in the different neurons of the spinal cord.

Animals↗