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M Endoh

Publications and source records attributed to M Endoh.

At least 289 records · Page 16Linked to original sources
PubMed1989

Kinetic studies of the pharmacologic response to captopril in rats. II. Hypotensive effect and plasma angiotensin converting enzyme activity.

The effect of captopril on the mean arterial blood pressure was studied in rats. Two different disease-state rats, namely the sodium-deficient rat (SDR) and the two-kidney-one-clip Goldblatt hypertensive rat (GHR), as well as normotensive rats (NR), were used. After i.v. bolus administration of captopril to each rat, the time course of plasma angiotensin converting enzyme (ACE) activity and mean arterial blood pressure were determined. In a different experiment, the effect of captopril on the plasma ACE activity in vitro was determined. Captopril inhibited the plasma ACE activity in a concentration-dependent manner and the relationship between concentration of captopril and inhibition of plasma ACE activity in vitro was reasonably described by a Langmuir-type equation. Then, plasma concentrations of captopril after i.v. administration were estimated by means of this equation. The estimated plasma concentration of captopril followed a double exponential equation. From the data obtained, a kinetic model including the renin-angiotensin system and pharmacokinetics of captopril was constructed under the following assumptions; (1) the hypotensive effect of captopril is solely attributable to the reduction of angiotensin II level in the body, (2) the production rate of angiotensin II is proportional to the total ACE activity and (3) plasma ACE activity reflects the total ACE activity in the body. Then, the effect of captopril on the mean arterial blood pressure in each type of rat was calculated. The results indicated that the hypotensive effect of captopril in NR was reasonably described by the model. However, the hypotensive effect of captopril in both GHR and SDR could not be well described by the model.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

Factors affecting sulfisoxazole transport through excised rat skin during iontophoresis.

Permeation of sulfisoxazole (SIX) across the excised rat skin were studied using two chamber cell with four electrodes, under three successive experimental conditions: without current for 3 h (treatment I), with current for 4 h (treatment II) and without current for 3 h (treatment III). Transport of SIX was significantly increased by iontophoresis. The enhancement ratio of SIX flux were reasonably predicted by Goldman's equation. There was no significant difference (p less than 0.05) between the flux in treatment I and treatment III. On the basis of the flux reversibility, it was concluded that skin alteration did not occur when the applied electric potential was below 5.025 V. Although a prominent current-induced volume flow (from the anodal side to the cathodal side) was observed during current exposure, SIX flux was not influenced by the volume flow. The flux enhancement of SIX was mainly dependent on transdermal potential difference.

Animals↗
PubMed1989

Relaxation of airway smooth muscle induced by potassium in the presence of Ca-antagonists.

We examined K+-induced relaxation instead of contraction in the presence of Ca-antagonists by measuring isometric tension in the tracheal smooth muscle isolated from guinea pigs. Cumulative administration of KCl (10-90 mM) induced a concentration-dependent contraction. When the muscle was pretreated with low concentrations of Ca-antagonists, cumulative administration of KCl caused a mild contraction, followed by a moderate relaxation. In the muscle pretreated with high concentrations of Ca-antagonists, KCl revealed a concentration-related relaxation without contraction. The potency ratios of Ca-antagonists to reverse the KCl-induced contraction to relaxation were nifedipine : verapamil : diltiazem = 94:4:1. This order of potency was quite similar to that of Ca-antagonists to relax the muscle precontracted with KCl (30 mM). Magnitudes of KCl (30 m,)-induced relaxation in the presence of Ca-antagonists were similar to those caused by Ca-antagonists in the KCl (30 mM)-precontracted muscles. Thus, K+-induced relaxation in the airway smooth muscle in the presence of Ca-antagonists may be due to the voltage-dependent increase in binding of Ca-antagonists to calcium channels.

Animals↗
PubMed1989

Three cases of acute massive hydrothorax complicating continuous ambulatory peritoneal dialysis (CAPD).

Acute hydrothorax is a rare complication of continuous ambulatory peritoneal dialysis (CAPD). We experienced three such cases among patients who started CAPD in our institute between April 1984 and April 1989. One was resolved with pleurodesis using autologous blood. The other two patients were switched to hemodialysis permanently because pleurodesis with autologous blood, tetracycline or OK432 failed. Acute hydrothorax is one important possible complication in CAPD.

Adult↗
PubMed1989

Long-term effect of urokinase therapy in IgA nephropathy.

Effects of urokinase (UK) therapy in patients with moderate to advanced degrees of IgA nephropathy (IgAN) were examined. Twenty-seven patients were treated by "two weeks" UK administration, 14 patients were treated by "consecutive" UK administration and 16 patients were treated by antiplatelet drugs. There were marked improvements in urinary protein concentration, serum creatinine and blood urea nitrogen after UK therapy, especially in patients treated by "consecutive" UK administration which was performed by "single shot" UK injection. Clinical prognosis was favorable in patients treated by UK administration compared with those given antiplatelet treatment. It was concluded that "consecutive" UK administration might be useful for treatment of IgAN with moderate to advanced renal injuries.

Adult↗
PubMed1989

Increase of IgA-specific switch T cells in patients with IgA nephropathy.

Enumeration and functional analysis of CD4+ T cells with receptors for the Fc portion of IgA (i.e. T alpha 4 cells) in the peripheral blood of patients with IgA nephropathy, their relatives and age-matched controls were performed to elucidate polyclonal activation of IgA production in this disease. Enumeration of T alpha 4 cells was performed by a fluorescence activated cell sorter, and functional analysis was carried out by separation of T alpha 4 cells, and IgM-, IgA- and IgG-bearing lymphocytes using panning methods followed by cultures of these cells for 7 days with pokeweed mitogen. There was a significant increase in the amount of peripheral blood T alpha 4 cells in patients with IgA nephropathy and their relatives. T alpha 4 cells specifically enhanced the switch of IgM-bearing cells to IgA-bearing cells, and this switch activity was inhibited by addition of human myeloma IgA. It is suggested that T alpha 4 cells may be responsible for polyclonal activation of IgA production in IgA nephropathy.

Adult↗
PubMed1989

Rapidly progressive glomerulonephritis undetected by routine school urinalysis: a case report.

A twelve year old girl with rapidly progressive glomerulonephritis (RPGN) is reported. First symptoms of renal failure developed in August 1987 just five months after a routine school urinalysis which detected no abnormalities. The patient developed end stage renal failure within 2 months of onset. Continuous ambulatory peritoneal dialysis (CAPD) was introduced to manage the renal failure, and open renal biopsy was performed simultaneously in order to elucidate the underlying renal disease in this patient. Microscopic examination of the biopsy specimen demonstrated marked formation of crescents in about 90% of the glomeruli, and some of the glomeruli were already sclerotic. Granular depositions of IgG(trace), IgA(1+), IgM(3+), properdine(3+), Clq(3+) and C3(3+) were observed by immunofluorescence staining. A definite diagnosis of rapidly progressive glomerulonephritis was made as the cause of renal failure in this patient. It was suggested that open renal biopsy is useful in diagnosing the underlying kidney disease of end stage renal failure in cases where the clinical course is relatively short.

Child↗
PubMed1989

Continuous ambulatory peritoneal dialysis in a diabetic patient with renal insufficiency and ventricular aneurysm.

A diabetic patient with renal insufficiency and a giant ventricular aneurysm was treated by continuous ambulatory peritoneal dialysis (CAPD). No apparent exacerbation of the patient's cardiovascular function was observed after starting CAPD therapy, although his ejection fraction remained low and his angina attacks persisted. It is suggested that CAPD therapy has no deleterious effects on the cardiovascular system of patients with ventricular aneurysms, and that the benefits outweigh the risks.

Angina Pectoris↗
PubMed1989

[Isolated fracture of the lateral mass of the atlas: a case report].

Isolated fracture of the lateral mass of the atlas is extremely rare. The authors report such a case because of its rarity and to emphasize the usefulness of computed tomography (CT) for its diagnosis. The case was that of a 63-year-old male, who had been hit on his left parietal region by a board falling from behind, and which forced him to hyperflex his neck. He complained of neck pain on arrival at our hospital without any resulting neurological deficits. Routine plain cervical spine films were normal, but CT scan revealed a vertical fracture of the lateral mass of the atlas. He was placed in a Halo brace for several months, and after 3 months the fracture was seen, by CT scan, to have healed without complications. Fractures of the atlas are uncommon. They comprise 2-13% of all fractures of the cervical spine, and about 1.3% of the fractures of the entire spinal column. An isolated fracture of the lateral mass of the atlas has been reported only in seven cases including our case previously and this is the first case in which CT scan could make the diagnosis. We emphasize that CT scan is a most useful tool for the diagnosis of the fracture.

Braces↗
PubMed1988

Further characterization of the myocardial alpha-adrenoceptors mediating positive inotropic effects in the rabbit myocardium.

[3H]Prazosin bound with high affinity to the membrane fraction derived from the rabbit ventricular myocardium. Oxymetazoline displaced [3H]prazosin from its binding site, did not elicit a positive inotropic effect but antagonized the positive inotropic effect of phenylephrine mediated by alpha-adrenoceptors in the presence of a beta-antagonist. Naphazoline was more potent in displacing [3H]prazosin and behaved as a weak partial agonist. YM-12617 (5-[2-[[2-(2-ethoxyphenoxy)ethyl]amino]propyl]-2- methoxybenzenesulfonamide HCl), a potent selective alpha 1-antagonist, displaced [3H]prazosin and antagonized the alpha-mediated positive inotropic effect with equal potency. Thus, a good correlation was found between the potency of alpha-antagonists to displace [3H]prazosin and their ability to antagonize the alpha-mediated positive inotropic effect. On the other hand, there was no significant correlation between the Ki and the pD2 value of the alpha-agonists (norepinephrine, epinephrine, phenylephrine and naphazoline), indicating that there is a non-linear relationship between agonist binding to myocardial alpha 1-adrenoceptors and subsequent functional changes. Myocardial alpha 1-adrenoceptors showed some pharmacological characteristics which appear to be different from those in smooth muscle tissues.

Adrenergic alpha-Agonists↗
PubMed1988

Phorbol ester does not mimic, but antagonizes the alpha-adrenoceptor-mediated positive inotropic effect in the rabbit papillary muscle.

The phorbol ester 12-O-tetradecanoyl phorbol-13-acetate (TPA) was used to examine the hypothesis that phosphoinositide turnover is involved in the regulation of myocardial contractility mediated by stimulation of alpha-adrenoceptors in the mammalian cardiac muscle. Exposure of the isolated rabbit papillary muscle electrically driven at a rate of 1 Hz at a temperature of 37 degrees C to TPA in concentrations of 10-1000 nmol/l for 30 min did not affect the basal force of contraction. The concentration-response curve for the positive inotropic effect of (-)-phenylephrine mediated by stimulation of alpha-adrenoceptors in the presence of (+/-)-bupranolol (100 nmol/l) was shifted to the right and downward by TPA in concentrations of 30-1000 nmol/l, while the effect of (-)-phenylephrine mediated by stimulation of beta-adrenoceptors in the presence of prazosin (100 nmol/l) was not decreased, but slightly enhanced by exposure of the muscle to relatively low concentrations of TPA (10-100 nmol/l). Incubation of the membrane fraction isolated from the rabbit ventricular muscle with TPA in vitro under the same condition as employed in the physiological experiments decreased the specific binding of [3H]prazosin but not that of [3H]CGP-12177, while the non-tumor promoting phorbol ester, alpha PDD, was ineffective. These results indicate that activation of protein kinase C by TPA does not mimic the positive inotropic effect of catecholamines mediated by activation of myocardial alpha-adrenoceptors.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenergic alpha-Antagonists↗
PubMed1988

Cytopathic effect of heat-labile toxin of Bordetella parapertussis on aortic smooth muscle cells from pigs or guinea pigs.

The in vitro effect of the heat-labile toxin (HLT) of Bordetella parapertussis on HeLa, baby hamster kidney (BHK), chinese hamster ovary (CHO), myeloma (Pa-NS-1), human embryonic lung (HEL-R66) cells, erythrocytes, adipocytes and lymphocytes from guinea pigs, mice or rats, or aortic smooth muscle cells from pigs or guinea pigs was examined. Within 8, 6, 4, 2, and 2 hr after the exposure to 1, 3, 10, 30, and 100 MNDs/ml of HLT, respectively, the cultured smooth muscle cells only showed a cytopathic change. When the cells exposed to HLT were washed out within 60 min post-exposure, the change could be induced with an extend period of lag. Histamine, KCl or norepinephrine caused similar change in the cells, but the period of lag was within 30 min. The HLT activity was neutralized by an anti-B. parapertussis- or B. bronchiseptica-HLT guinea pig IgG. HLT had no effects on any other cells tested.

Animals↗
PubMed1988

Contractile action of heat-labile toxin of Bordetella parapertussis on aortic smooth muscles of pigs.

Using both vascular smooth muscle strips (VSMS) and cultured cells (VSMC) from aortas of pigs, the contractile action of Bordetella heat-labile toxin (HLT) purified from B. parapertussis was studied in an attempt to elucidate the mechanisms of its action. HLT induced contractions in VSMC in parallel with the increase of Ca2+-influx. The HLT-induced Ca2+-influx and contraction were not influenced by verapamil or diltiazem, though a certain extension of the lag period was seen. The contractile action of HLT on VSMS and VSMC was not influenced either by diltiazem or quinacrine; that on VSMC was not influenced by prednisolone, indomethacin, aspirin, CV-3988, FPL-55712, ruthenium red, or TEAC. On VSMS, prednisolone caused the extension of lag period following HLT exposure. The action of HLT on VSMS was inhibited by TMB-8, whereas that on VSMC was not though the extension of lag period was seen. The HLT-induced contraction in both VSMS and VSMC was completely inhibited by H-7. The contraction in VSMS, but not in VSMC, was inhibited by H-8. HLT did not induce specific activation of the protein kinases in VSMC. The addition of cGMP or cAMP brought about relaxation in the HLT-exposed VSMS contracting in maximum. HLT caused a significant increase in permeability of VSMC membrane to trypan blue, accompanied with contraction. Both HLT-induced contraction and increase in permeability were inhibited by dextran of M.W. 8,000, but not of M.W. 5,000. These results suggested that HLT acted on vascular smooth muscle cells by damaging the membrane permeability, but not by disturbing the known cascades or systems for physiological contractions, resulting in the increase in Ca2+-influx and then contractions.

Animals↗
PubMed1988

Levels of circulating IgA immune complexes after gluten-rich diet in patients with IgA nephropathy.

Measurement of IgA circulating immune complexes (IgA-CIC) in sera from patients with IgA nephropathy after a gluten-poor diet, an unrestricted diet and a gluten-rich diet is described. High levels of IgA-CIC in sera were detected in patients after these diets. However, the levels of IgA-CIC in sera 2 weeks after the gluten-rich diet were not significantly increased compared with those after the other diets. It is suggested that, for a short duration, the gluten-rich diet might not increase the levels of IgA-CIC in sera from Japanese patients with IgA nephropathy.

Adolescent↗