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A Inoue

Publications and source records attributed to A Inoue.

At least 469 records · Page 26Linked to original sources
PubMed1986

Acute effects of captopril on the baroreflex of normotensive and spontaneously hypertensive rats.

When captopril was injected intravenously in urethane anesthetized rats, a hypotensive effect accompanied by bradycardia was obtained, while an intravenous (i.v.) injection of prostaglandin I2 (PGI2), which induced hypotension of the same magnitude as the hypotensive effect obtained with captopril, caused a marked tachycardia. Simultaneously, sympathetic nerve activity recorded from abdominal sympathetic nerves was unchanged following injection of captopril, while it was significantly increased during hypotension induced by PGI2. The bradycardia, but not the hypotensive effects induced by captopril was abolished by i.v. pretreatment with atropine. Intracisternal injection of a small dose of captopril inhibited reflex tachycardia during hypotension induced by PGI2 and prolonged the hypotensive effect, while intravenous administration of this dose did not inhibit the reflex tachycardia induced by PGI2. In spontaneously hypertensive rats (SHR), the hypotensive effect of captopril was increased partly, however, the accompanying bradycardia was significantly reduced. These findings suggest that captopril inhibits the baroreflex and centrally activates the cardiac vagal nerve. Moreover in SHR, the effect of captopril on cardiac vagal activity was disturbed.

Animals↗
PubMed1986

Different kinetics of antiviral and anticellular activities between human recombinant and natural interferon-gamma arising from different receptor-binding properties.

Human recombinant interferon-gamma (ReIFN-gamma) and human natural interferon-gamma (IFN-gamma) showed significant differences in antiviral and anticellular activities. Namely, ReIFN-gamma exhibited antiviral activity against Sindbis virus and anticellular activity against HeLa S3 cells at significantly lower concentrations as compared with IFN-gamma at short exposure times of between 1 and 4 hr. This difference of activities was explicable in terms of different binding activities of the two IFNs to the receptors. The binding of 125I-ReIFN-gamma to the receptors was competitively decreased in a dose dependent manner by unlabeled ReIFN-gamma, whereas the competition by unlabeled IFN-gamma was significantly weaker. The results of pretreatment of the cells with unlabeled ReIFN-gamma or IFN-gamma suggested that the binding of IFN-gamma to the receptors was slower than that of ReIFN-gamma. ReIFN-gamma and IFN-gamma exhibited greater colony formation-inhibitory activity against HeLa S3 cells, as compared with IFN-alpha or ReIFN-beta. ReIFN-gamma also inhibited DNA, RNA and protein syntheses of HeLa S3 cells more potently than ReIFN-beta. However, the 2'-5' oligoadenylate (2'-5' A) synthetase activity in ReIFN-gamma-treated cells was significantly lower than that in ReIFN-beta-treated cells, suggesting that 2'-5' A synthetase does not play a major role in the anticellular activity of ReIFN-gamma, at least against HeLa S3 cells.

2',5'-Oligoadenylate Synthetase↗
PubMed1986

Central GABA-ergic stimulation attenuates hypertension and hypothalamic hyperactivity in spontaneously hypertensive rats.

When GABA (4-amino-n-butyric acid, 50-200 micrograms) was injected into the lateral ventricle of urethane-anaesthetized Wistar rats, sympathetic nerve activity, arterial pressure and heart rate were decreased dose-dependently. Graded electrical stimulation of the ventromedial hypothalamus (50, 100 and 150 microA) increased not only mean blood pressure but also the rate of sympathetic nerve firing, and both responses were attenuated by GABA pretreatment (100 and 200 micrograms, i.c.v.). In spontaneously hypertensive rats (SHR), i.c.v.-injected GABA also reduced sympatho-cardiovascular activity, but the magnitude of the depressor responses was significantly larger in SHR than in normotensive Wistar-Kyoto (WKY) control rats. Pressor and sympathetic nerve responses elicited by hypothalamic stimulation were initially larger in SHR than in WKY rats. However, upon subsequent i.c.v. injection of GABA, hypothalamic responsiveness in SHR was inhibited more prominently and became almost the same as that in WKY rats. These results suggest that, by depressing hypothalamic function, central GABA-ergic stimulation decreases sympathetic nerve activity thereby lowering blood pressure and heart rate. Because of the increased central sensitivity in SHR, GABA-ergic stimulation reversed hypothalamo-sympathetic hyperactivity and attenuated hypertension.

Animals↗
PubMed1986

[High performance liquid chromatographic determination of astromicin and cefsulodin used in combination in blood samples].

Aminoglycoside and beta-lactam antibiotics are often used in combination. This paper reports a high performance liquid chromatographic determination method for each of astromicin (ASTM) and cefsulodin (CFS) in blood samples of several species. The procedure for ASTM included purification with CM-Sephadex, separation on a reversed phase column (C-18) and derivatization with o-phthalaldehyde (OPA). The procedure for CFS included deproteinization with methanol, centrifugation, filtration and separation on a reversed phase column (C-18). Either of the drugs did not affect the determination of the other. The detection limits were 0.1 microgram/ml for ASTM and 0.5 microgram/ml for CFS. These sensitivities seem good enough for a clinical application of the method considering usual dosage levels of the drugs.

Aminoglycosides↗
PubMed1986

[High performance liquid chromatographic determination of astromicin and cefoperazone used in combination in blood samples].

Combination therapy of aminoglycoside and beta-lactam antibiotics is often used clinically because of its effectiveness. This paper reports a high performance liquid chromatographic (HPLC) determination method for each of astromicin (ASTM) and cefoperazone (CPZ) in blood samples of several species. The procedure for ASTM included purification with CM-Sephadex, separation on a reversed phase column (C-18) and derivatization with o-phthalaldehyde (OPA). The procedure for CPZ included deproteinization with methanol, centrifugation and separation on a reversed phase column (C-18). Either of the drugs did not affect the determination of the other. The detection limits were 0.1 microgram/ml for ASTM and 0.5 microgram/ml for CPZ. These sensitivities seem good enough for a clinical application of the method considering usual dosage levels of the drugs.

Aminoglycosides↗
PubMed1986

[High performance liquid chromatographic determination of astromicin and piperacillin used in combination in blood samples].

Aminoglycoside and beta-lactam antibiotics are often used in combination, and many synergistic effects have been reported. We describe here a high performance liquid chromatographic determination method for each of astromicin (ASTM) and piperacillin (PIPC) in blood samples of several species. The procedure for ASTM included purification with CM-Sephadex, separation on a reversed phase column (C-18) and derivatization with o-phthalaldehyde (OPA). The procedure for PIPC included deproteinization with acetonitrile, centrifugation and separation on a reversed phase column (C-18). Either of the drugs did not affect the determination of the other. The detection limits were 0.1 microgram/ml for ASTM and 0.5 microgram/ml for PIPC. These sensitivities seem good enough for a clinical application of the method considering usual dosage levels of these drugs.

Aminoglycosides↗
PubMed1986

[The pharmacokinetic studies on astromicin in dogs. Intramuscular, intravenous or drip intravenous administration].

The pharmacokinetics of astromicin (ASTM), a new aminoglycoside antibiotics, was studied in dogs after intramuscular (i.m.), intravenous (i.v.) or drip intravenous (d.i.v.: for 0.5, 1 hr. or 2 hrs.) administration at a dose of 20 mg/kg. The pharmacokinetic parameters were calculated using one-compartment open model (i.m.) or two-compartment open model (i.v. and d.i.v.). The peak plasma levels of ASTM were 34.1 mcg/ml (i.m.), 50.5 mcg/ml (d.i.v., 0.5 hr.), 39.8 mcg/ml (d.i.v., 1 hr.) and 28.2 mcg/ml (d.i.v., 2 hrs.), respectively. The pharmacokinetic parameters (T1/2, AUC infinity, Kel, Vd and Cl) of ASTM except Cmax and Tmax were similar for different routes of administration. Urinary recovery rates of ASTM were 90.5% (i.m.), 95.2% (i.v.), 91.6% (d.i.v., 0.5 hr.), 92.6% (d.i.v., 1 hr.) and 93.5% (d.i.v., 2 hrs.) by 24 hours. After intramuscular, intravenous or 1 hour drip intravenous administration of ASTM, no active metabolite was found in urine of dogs.

Aminoglycosides↗
PubMed1986

[A phase I study on intravenous drip infusion of astromicin].

A phase I study on intravenous drip infusion of astromicin (ASTM, KW-1070), an aminoglycoside antibiotic, was performed on 9 healthy adult male volunteers to investigate the safety and pharmacokinetics of this drug. ASTM 200 mg was dissolved in 250 ml of saline and given to each of 6 volunteers by drip infusion in 1 hour. For comparison, 200 mg of ASTM in 1 ml of saline was injected intramuscularly. No subjective and objective reactions were found, and laboratory test value did not show any change possibly caused by ASTM. In a single administration study, Cmax was 10.8 micrograms/ml by intramuscular injection and 12.0 micrograms/ml by intravenous drip infusion. The areas under the time-serum concentration curve were 35.6 micrograms X hr/ml and 34.9 micrograms X hr/ml, respectively; that is, the serum levels of ASTM after one-hour intravenous drip infusion changed almost identically to those after intramuscular injection. In a multiple administration study, the change in serum levels of ASTM after the ninth administration was approximately the same as that after the first one. This means that no accumulation of ASTM in serum occurred. Recovery rates of ASTM in urine up to 8 hours after a single intramuscular injection and a single intravenous drip infusion were 85.4% and 87.5%, respectively. These results also support the conclusion that there is no accumulation of ASTM in the body by repeated administrations.

Adult↗
PubMed1986

[Pharmacokinetic studies of astromicin using a constant-rate continuous intravenous infusion method].

Astromicin (ASTM) was administered intravenously to 4 healthy adult volunteers with an average body weight of 62 kg using a continuous infusion apparatus at a constant rate of 200 mg in 1 hour (Group I), 400 mg in 1 hour (Group II) and 200 mg in 2 hours (Group III). Concentrations of the drug in serum and urine were determined by high power liquid chromatography (HPLC). The mean serum concentration of the 4 subjects reached the peak of 13.32 micrograms/ml in Group I, 22.12 micrograms/ml in Group II and 9.89 micrograms/ml in Group III. The peak concentration was achieved at the end of infusion and was dose-related. After 8 hours, the concentration dropped to less than 1 micrograms/ml in all groups. The urinary recovery rate was 90% in 8 hours and 95% in 24 hours. T1/2 (beta) analyzed by the two-compartment open model was 1.64-1.72 hours. AUC infinity was also dose-related, such as 33.1 micrograms X hr/ml and 31.6 micrograms X hr/ml in Group I and Group III, and 57.6 micrograms X hr/ml in Group II. It is recommended for amikacin (AMK) that the peak serum concentration should not exceed 35 micrograms/ml and the maximum concentration before the next infusion should be less than 5 micrograms/ml. In these experiment, ASTM which is lower in toxicity than AMK did not approach 35 micrograms/ml even at the peak level with the dosage of 400 mg in 1 hour. Furthermore, the excretion of the drug was fast and the serum level of the drug became much lower than 5 micrograms/ml very quickly.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1986

[Pharmacokinetics of astromicin intravenous drip infusion in patients with renal disorders].

Astromicin (ASTM), a new aminoglycoside antibiotic, was administered to 7 patients with renal disorders. Concentrations of ASTM in blood were determined for pharmacokinetic analysis. ASTM was administered by intravenous drip infusion over 1 hour at a dose of 200 mg to each of 6 patients and at a dose of 100 mg to 1 patient. Renal function was observed by the clearance of intrinsic creatinine (Ccr) as the indicator. Concentrations of ASTM in blood became higher and retention times longer as degrees of the loss of renal function were larger. Although ASTM is proved to be one of drugs with the highest degree of safety compared with other existing aminoglycoside antibiotics, it should be administered with care to patients with renal disorders.

Adult↗