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E Sugimoto

Publications and source records attributed to E Sugimoto.

At least 73 records · Page 4Linked to original sources
PubMed1990

Luminal CCK-releasing factors in the isolated vascularly perfused rat duodenojejunum.

The factors operating at the apical side of the endocrine cell releasing cholecystokinin (CCK) were investigated using the isolated vascularly perfused rat duodenojejunum. In the protease-free intestinal segment, a 30-min infusion of glucose (280 mM), oleic acid (100 mM), or triglycerides containing short- or long-chain fatty acids did not alter significantly the basal level of portal CCK-like immunoreactivity (CCK-LI), while octanoic acid (100 mM) produced a transient rise of plasma CCK-LI to approximately 250% of basal. Infusion of proteins (5% solutions of ovalbumin or casein) or of a mixture of all amino acids brought about a modest CCK secretion. In contrast, isocaloric amounts of an ovalbumin hydrolysate produced a sharp rise of portal CCK-LI to 530% of basal followed by a well-sustained plateau secretion (420% of basal) until the end of the infusion. An acid casein hydrolysate induced a slightly less pronounced CCK-LI release and was followed in decreasing order by meat, casein, and soybean peptones. Simultaneous infusion of trypsin with ovalbumin or casein hydrolysate reduced by approximately 60% the CCK release induced by peptone alone. This effect was reversed by coinfusion of soybean trypsin inhibitor (SBTI) with the trypsin-peptone mixture. Arterial infusion of tetrodotoxin (10(-6) M) or atropine (10(-5) M) had no significant effect on the trypsin-induced inhibition of peptone-mediated CCK-LI release. Administration of SBTI or camostate alone or in combination with trypsin did not alter basal CCK. Monitor peptide produced a dose-dependent transient rise of portal CCK-LI over the range from 2 to 12 micrograms.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acids↗
PubMed1989

Differentiation of intestinal epithelial cell line (IEC-18) by an acid extract of rat small intestine.

A factor which may induce differentiation of intestinal epithelial cell lines in vitro was found in an acid extract of adult rat small intestine. The addition of a partially purified acetic acid extract of rat small intestine to IEC-18 cell culture dishes increased sucrase activity within 48 h. Thymidine incorporation markedly decreased within 24 h. Significant development of microvilli-like structures was observed on the acid extract-treated IEC-18 cells, compared with controls. This activity of rat acid extract was heat-stable and the apparent molecular weight of the factor was 400-800. These findings suggested that the factor may be related to the epithelial differentiation of rat small intestinal crypt cells.

Animals↗
PubMed1989

Effect of ANP on circulating blood volume.

The effects of rat atrial natriuretic peptide (rANP) on blood volume (BV) were determined by the continuous measurement of BV, mean arterial pressure (MAP), and central venous pressure (CVP). Immediately after a single-bolus injection of rANP-(1-28), 1 nmol/100 g body wt, in conscious rats, BV began to decrease. Peak reduction of -0.22 +/- 0.03 ml/100 g body wt was reached 14.5 min after the injection. Thereafter, BV levels returned gradually to -0.08 +/- 0.03 ml/100 g body wt compared with the control value. In volume expansion experiment, the nephrectomized, anesthetized rats were divided into two groups: the control group, with only a saline infusion, and the ANP group, with an infusion of saline with rANP (1 nmol/100 g body wt). In the ANP group, increases in BV were not as great, and recovery was threefold faster than that of the control group. In the ANP group, the recovery time of BV to the starting control levels was 8.5 min, and the time constant of recovery was 3.6 +/- 0.3 min-1. The control group times were 25 min and 11.5 +/- 0.8 min-1, respectively. The effective vascular compliances were approximately 2.8 ml.mmHg-1.kg body wt-1 in both groups, and the capillary filtration coefficient was 0.47 ml.mmHg-1.min-1.kg body wt-1 in the ANP group and 0.33 ml.mmHg-1.min-1.kg body wt-1 in the control group. Thus the whole body capillary filtration coefficient was 1.5-fold higher in the ANP group than in the control group. This suggests that ANP may increase the permeability of capillaries.

Animals↗
PubMed1988

Changes in blood volume and vascular compliance during body heating in rats.

The effects of hyperthermia on blood volume and effective vascular compliance were studied in control and heat acclimated rats (three weeks at 32 degrees C and 50% R.H.). Experiments were performed on conscious rats whose abdominal aorta and both jugular veins were cannulated. Continuous changes in blood volume (BV) were monitored by measuring 51Cr tagged erythrocyte dilution, using an arterio-venous extracorporeal shunt passing through a gamma counter. Total vascular compliance was calculated from the relation between changes in BV and central venous pressure during 10 min of infusion of saline at a rate of 1.6% body wt/10 min. Hyperthermia induced a significant blood volume expansion. This expansion was more pronounced in non-acclimated rats. Effective vascular compliance was similar in the normothermic, both non-acclimated and acclimated rats. However, while hyperthermia did not affect the vascular compliance of non-acclimated rats, it was decreased significantly in the acclimated hyperthermic rats. The data suggest that changes in vascular compliance play a role when rapid blood volume changes take place, especially in acclimated hyperthermic animals. The relations between changes in vascular compliance and heat induced redistribution of cardiac output are discussed.

Acclimatization↗
PubMed1988

Analysis of salt and water intake by continuous determination of blood volume and plasma sodium concentration.

Seven rats were exposed to a hot environment (36 degrees C) for about 5 h to induce thermal dehydration. They were allowed to recover from their fluid loss; both tap water and 1.8% NaCl solution were provided simultaneously as drinking fluids. In the recovery stage, these animals initially consumed low NaCl solution (about 41 mEq/l) for the first 90 min and then shifted to drinking slightly hypotonic NaCl solution (about 122 mEq/l) on the average. To analyze the mechanism driving the above shift, changes in blood volume (BV), plasma Na concentration ([Na]), and the amount of water and 1.8% NaCl solution consumed were measured continuously. After 4 h of recovery, BV increased by +1.1 ml/100 g body wt. and reached 5.7 ml/100 g body wt. (set as 100%) while plasma [Na] reduced by -5.5 mEq/l or to 141.5 mEq/l (mean values of 7 rats). The shift of [Na] of drinking water was observed when plasma [Na] reduced to -3.4 mEq/l or 62.3% of the 4th-hour level, while BV recovery remained only +0.5 ml or 46.3%. A response to urinary output started later when plasma [Na] reached 142.6 mEq/l or 83.1%, while BV recovery remained +5.4 ml or 76%. These results indicate that the regulation of plasma [Na] takes precedence over the regulation of BV. This conclusion is in agreement with the view that the blood osmolality change directly modifies the cell volume whereas circulatory function under decreased blood volume can be regulated by change of the vascular compliance.

Animals↗
PubMed1988

[Radiologic detection of metastatic bone tumors].

Radiologic strategy for early detection of bone metastasis is discussed. Incidence, pathway, and radiologic manifestation of bone metastasis are briefly discussed. Bone scintigraphy is a mainstay for early detection of bone metastases, although its role as a part of staging procedure is debatable. Plain radiograph and CT scan are to be used to increase specificity of scintigraphic findings. For detection of spinal metastases CT scan is particularly useful and should be used whenever spinal metastases are suspected. MRI has become an important modality to see an extraosseous extension and marrow invasion of metastatic bone tumor.

Bone Neoplasms↗
PubMed1987

Lithium ion reversibly inhibits inducer-stimulated adipose conversion of 3T3-L1 cells.

Adipose conversion of 3T3-L1 cells by inducers (dexamethasone, 1-methyl-3-isobutylxanthine and insulin) was inhibited by LiCl at concentrations from 2 to 20 mM. The effect of LiCl was reversible and the inhibited cells were converted to adipocytes when stimulated after the removal of LiCl. Inhibition by LiCl of adipose conversion was accompanied with a blockage of the enhanced [3H]thymidine incorporation and cellular proliferation that occurred before the adipocyte phenotype was expressed. Of the cations tested, only Li+ had these effects.

1-Methyl-3-isobutylxanthine↗
PubMed1987

Competition of a growth stimulating-/cholecystokinin (CCK) releasing-peptide (monitor peptide) with epidermal growth factor for binding to 3T3 fibroblasts.

The growth stimulating-/cholecystokinin (CCK) releasing-peptide (monitor peptide) is a peptide purified from rat bile-pancreatic juice on the basis of its stimulatory activity toward pancreatic enzyme secretion. Its multiple functions and peptide sequence suggested that it is distinct from epidermal growth factor (EGF). However, we found that the peptide competes with [125I]-EGF in the binding to Swiss 3T3 fibroblast cells to almost the same extent as unlabeled EGF does. [125I]-EGF binding was inhibited by 50% by the peptide at 82.8 ng/ml and by unlabeled EGF at 71.4 ng/ml. This suggests that the growth stimulating effect of the peptide on 3T3 fibroblasts is mediated via the EGF receptor, and also suggests that the partial homologous sequence between monitor peptide and EGF is required for the receptor binding, or that the EGF receptor has a broad ligand specificity.

Amino Acid Sequence↗
PubMed1987

Iodine-123 IMP SPECT before and after bypass surgery in a patient with occlusion of left anterior and middle cerebral arteries with basal abnormal telangiectasis (unilateral Moyamoya disease).

A case of left anterior and middle cerebral arterial occlusion with angiographic features similar to Moyamoya disease was reported. IMP SPECT of the patient revealed the success of bypass surgery clearly. The patient complained of transient right hemiparesis with aphasia 4 times. The cerebral arteriography disclosed occlusions of left anterior and middle cerebral arteries at their proximal portions. Right internal carotid and its branches were normal. I-123 IMP SPECT study showed hypoperfusion in left temporal lobe, basal ganglia with incomplete reperfusion on the delayed (4 hours after injection) SPECT images. After the superficial temporal-middle cerebral artery anastomosis, I-123 IMP SPECT showed improvement of the brain blood flow. I-123 IMP SPECT was very useful in detecting the ischemic areas and evaluating the revascularizing surgery in this case.

Adult↗
PubMed1987

Reversible interconversion between primitive endoderm- and parietal endoderm-like F9 cells demonstrated by mRNAs expression.

The differentiation of retinoic acid-treated F9 cells (primitive endoderm-like F9 cells) into parietal endoderm-like F9 cells induced by dibutyryl cAMP was studied as a culture model of the morphogenesis of early mouse embryo. For this purpose, 6 cDNA clones coding for mRNAs specifically expressed in parietal endoderm-like F9 cells were selected. Northern hybridization of RNA extracted from variously treated F9 cells to nick-translated plasmid DNA of these clones demonstrated the reversible expression of many mRNAs depending on the presence of dibutyryl cAMP in the culture medium. This result suggested that the differentiated state of parietal endoderm, which is formed from primitive endoderm at a position adjacent to the trophectoderm in mouse embryo, can be reversed if the local signal is removed. One of the selected clones, pLAM, hybridized to an mRNA of 6.3 kb and selected mRNA producing a laminin B subunit in an in vitro translation system. This clone has an inserted sequence of 3.1 kb. Among the restriction sites in this sequence, six were consistent with those in a 1.7 kb inserted sequence of pPE 49 and pPE 386, which were isolated by Barlow et al. as laminin B1 clones. An XbaI site found in both pPE 49 and pPE 386 was, however, not found at the corresponding position of pLAM. Dot hybridization of RNA with pLAM showed that expression of laminin B in F9 cells is stimulated more than 100-fold during differentiation of F9 stem cells into parietal endoderm-like F9 cells.

Animals↗
PubMed1987

Changes in blood volume and plasma sodium concentration after water intake in rats.

Changes in blood volume (BV) and Na+ concentration of plasma ([Na+]) were measured continuously during recovery from thermal dehydration in rats. At least 5 days prior to the experiments rats were cannulated into both the jugular vein and the descending aorta. After thermal dehydration (DBT: 36 degrees C, RH: 20%) amounting to approximately 6% of body wt, catheters were connected to a system for continuous monitoring of BV and [Na+]. Water was made available and water intake, BV, and [Na+] were recorded at 30-s intervals for 4 h. The rats took 2-3 ml of water/100 g of body wt in the first 10 min and then drank 1 ml at 30- to 60-min intervals to reach equilibrium in 2-3 h. The relations between water intake and delta BV and between delta[Na+] were analyzed for 2 h after the start of water supply. BV was unchanged until 18.9 +/- 3.6 min after access to water, whereas [Na+] started to decrease after 3.6 +/- 0.6 min. The retention ratio of ingested fluid in the vascular space was 20.8 +/- 2.8%, and the decrease of [Na+] was 1.5 +/- 0.2 meq X l-1 X ml ingested fluid-1 X 100 g body wt-1. These results indicate that drinking causes the change of [Na+] more rapidly than that of blood volume.

Animals↗
PubMed1986

Growth stimulating activity on 3T3 fibroblasts of the molecular weight 6,500-peptide purified from rat pancreatic juice.

Growth stimulating activity of the molecular weight 6,500-peptide purified from rat pancreatic juice was measured on 3T3 fibroblasts. This peptide was reported to be a cholecystokinin-releasing peptide and to stimulate pancreatic enzyme secretion in the rat small intestine in response to food intake. Incorporation of [3H]thymidine and [35S]methionine into 3T3 was significantly stimulated and the cell number was also increased after 24-48 hr incubation with 10-100 ng/ml of the peptide. The increase in [3H]thymidine incorporation was dose-related and started 12 hr after the incubation, a peak being reached 24 hr after the incubation. These results show that this peptide exhibits growth stimulating activity to the mammalian cells, and suggest that the peptide might have a physiological effect in vivo.

Animals↗
PubMed1986

Continuous recording of plasma sodium concentration and blood volume in awake rats.

A new continuous measuring system for blood sodium concentration and blood volume in conscious rats is described. A small extracorporeal circulation was made and the blood was passed through a sodium sensitive glass electrode and a gamma-counter. Applying the system to conscious rats, the effect of various salinities of drinking water was detected from the change in blood sodium concentration.

Animals↗
PubMed1985

Interaction between glucocorticoids, 8-bromoadenosine 3',5'-monophosphate, and insulin in regulation of synthesis of carbamoyl-phosphate synthetase I in Reuber hepatoma H-35.

Regulation of synthesis of carbamoyl-phosphate synthetase I by glucocorticoids, 8-bromoadenosine 3',5'-monophosphate (8-bromo-cAMP), and insulin was investigated in Reuber hepatoma H-35. By measuring the incorporation of [35S]methionine into carbamoyl-phosphate synthetase I and its precursor, we showed that dexamethasone stimulates the enzyme synthesis approximately fivefold. A detectable stimulation was observed at 1 nM of dexamethasone, half-maximal stimulation at 4 nM, and maximal stimulation above 40 nM. Corticosterone was more effective than dexamethasone both for the minimal concentration needed and for the extent of the stimulation. Hydrocortisone was less effective than dexamethasone. 8-Bromo-cAMP also stimulated the enzyme synthesis at a concentration of 3 mM. The effect of 8-bromo-cAMP was suggested to be additive to the effect of dexamethasone. Physiological concentrations of insulin strongly suppressed the stimulatory effect of dexamethasone on the enzyme synthesis but could not completely counteract the effect of dexamethasone. The half-maximal and maximal effects of insulin were observed at 0.5 nM and 5 nM, respectively. Insulin also counteracted the effect of 8-bromo-cAMP on the enzyme synthesis.

8-Bromo Cyclic Adenosine Monophosphate↗
PubMed1985

Post-translational assembly and glycosylation of laminin subunits in parietal endoderm-like F9 cells.

Non-reducing and reducing sodium dodecyl sulphate/polyacrylamide-gel electrophoresis of laminin synthesized in parietal endoderm-like F9 cells demonstrated that only AB1B2 complex goes through intracellular traffic for oligosaccharide side-chain processing and secretion. Glycosylation was not necessary for subunit assembly. Assembly was suggested to proceed through B1B2 to AB1B2. Among the pools of monomer subunits, the B2 pool was smallest.

Cell Line↗
PubMed1985

Reversible effects of dibutyryl cAMP on laminin and type IV collagen secretion from retinoic acid treated F9 cells.

The effects of dibutyryl cAMP on the differentiation of embryonal carcinoma F9 cells were studied mainly using the secretion of laminin and type IV collagen as the marker. For this purpose, F9 cells were labeled with 35S-methionine and radioactive proteins in the medium were analyzed by SDS-polyacrylamide gel electrophoresis. Treatment of F9 cells with retinoic acid alone induced differentiation into cells secreting type IV collagen. The combination of retinoic acid and dibutyryl cAMP stimulated laminin secretion in addition to type IV collagen secretion. This effect of dibutyryl cAMP was observed only 16 h after adding dibutyryl cAMP. Immunofluorescence staining demonstrated that the majority of the cells in culture were converted into cells secreting laminin under these conditions. In contrast to the irreversible effect of retinoic acid, the effect of dibutyryl cAMP on laminin and type IV collagen secretion was reversible at least during the first 5 days of maintaining cells in the medium containing retinoic acid plus dibutyryl cAMP. Removal of dibutyryl cAMP from the culture medium decreased the protein secretion to the basal levels within 2 days. This reversibility was not due to a change in cell number. An in vitro translation assay also suggested the reversible effect of dibutyryl cAMP on the levels of laminin mRNA. Coinciding with variations of the protein secretion, a reversible and homogeneous change in the morphology of retinoic acid generated F9 cells was observed by dibutyryl cAMP.

Animals↗
PubMed1985

Abnormal laminin secretion from parietal endoderm-like F9 cells in the presence of monensin.

We studied the effects of monensin on post-translational modification and intracellular transport of precursors of laminin subunits in parietal endoderm-like F9 cells. At concentrations higher than 0.1 microM, monensin inhibited the processing of high-mannose type precursors for all three subunits and caused their cytoplasmic accumulation. Furthermore, the secretion of mature subunits of laminin was inhibited. Instead, polypeptides with similar molecular weights to those of intracellular precursors were secreted. These polypeptides were immunologically related to laminin subunits and were sensitive to digestion with beta-N-acetylglucosaminidase H (Endo H). This indicated that Golgi complexes of the cells can transport the precursors of laminin subunits even with their terminal glycosylation inactivated by monensin. Tunicamycin induced the accumulation of unglycosylated precursors and strongly reduced their secretion into the medium.

Animals↗