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T Tadano

Publications and source records attributed to T Tadano.

At least 109 records · Page 6Linked to original sources
PubMed1977

Pharmacological actions of intracerebrally administered polyamines in mice.

Pharmacological actions of spermidine (SPD) and spermine (SPM) in mice given these polyamines by intracerebral injection (i.c.) were investigated. The spontaneous motor activity (SMA) assessed by the photocell counter method did not change immediately following injection of 80 mug SPD, but was enhanced 24 hours after the injection of 40 or 80 mug. A significant decrease of SMA was not immediately evident after the administration of 40 mug SPM but was demonstrated 24 hours later. Mice given single doses of 20 mug SPD exhibited increase in weight gain and those given 40 mug showed no significant difference, whereas a conspicuous decrease in weight occurred in mice given 80 mug of SPD. The body weights of mice given single doses of 10 mug SPM remained much the same, while significant weight losses occurred in both the SPM 20 mug and 40 mug dosed groups. There was a significant prolongation of pentobarbital induced sleep 6 days after the injection of high doses of SPD or SPM. Similar prolongation of sleeping time was also evident 30 minutes after the injection of SPM. A maximal hypothermic response with a fall by about 1 degree C was observed immediately following injection of 80 mug of SPD and 24 hours after the injection of 40 mug SPM, respectively.

Animals↗
PubMed1977

[Central action of beta-phenylethylamine derivatives (10). Effect of L-Dopa on metaraminol induced motor activity (author's transl)].

The present experiments were undertaken in investigate the effects of Ro4-4602 plus L-Dopa on biphasic action induced by metaraminol (MA) in mice. The following results were obtained: Spontaneous motor activity (SMA) suppressed by MA was recovered by pretreatment of Ro4-4602 plus L-Dopa and increased by more than 100 mg/kg of L-Dopa. However, SMA was increased by more than 400 mg/kg of L-Dopa in saline pretreated mice. In MA pretreated mice, SMA by L-Dopa markedly increased in proportion to the doses of MA. The peak time of SMA by L-Dopa in MA pretreated mice was observed to be faster than that in saline pretreated mice. When L-Dopa was injected into MA and saline pretreated mice, there was no significant difference of brain dopamine content between the two groups. From the above results, it is considered that the enhanced effect of L-Dopa in MA pretreated mice may be due to production of a supersensitivity to catecholamines in the central nervous system. MA induced hyper-motor activity was enhanced by pretreatment of Ro4-4602 plus L-Dopa which have no influence on SMA.

Animals↗
PubMed1977

[Central action of beta-phenylethylamine derivatives (9). Effects of intracerebral administration of metaraminol on brain monoamine in mice (author's transl)].

Effects of intracerebral (i.c.) administration of metaraminol (MA) on brain monoamine in mice were studied. The results were as follows: MA, dopamine (DA), noradrenaline (NA) and 5-hydroxytryptamine (5-HT) were separated with phosphate buffer using a phosphorylated cellulose column (1X11 cm, 9 ml, Lot No. 2809). When MA was i.c. injected into mice, fluorescence of MA at 275/305 nm decreased in proportion to the time course and remained even at 12 hr after injection. Thirty min after MA in doses of either 40 or 80 microgram, a significant decrease of DA as compared with that of saline-treated group occurred and MA, in doses of 40, 80 and 160 microgram produced a significant decrease of NA and 5-HT. Thirty min after 160 microgram of MA, there was no significant difference in DA. Three hr after MA, DA levels significantly decreased, and 168 hr after were restored to the levels of the saline-treated group. Thirty min after MA, NA and 5-HT signficantly decreased compared with those of the saline-treated group and recovery took place 48 hr and 168 hr after respectively. It was concluded that MA depletes not only NA but also DA and 5-HT in the mouse brain.

Animals↗
PubMed1975

Effects of polyamines on the central nervous system.

Effects of polyamines on the central nervous system were studied in mice. Intraperitoneal administration of Spermidine (SPD) and Spermine (SPM) decreased spontaneous motor activity as measured by either the photo-cell counters method or the open-field test and lowered rectal temperature. A significant prolongation of sleeping time after pentobarbital was confirmed in small doses of SPD and SPM which had slight influence on spontaneous motor activity. The time to convulsion and death induced by strychnine was elongated by SPD and SPM. SPM in small doses inhibited writhing responses induced by 0.7% acetic acid. In addition, methamphetamine-induced hyperactivity and conditioned avoidance response were blocked by SPM in doses which decreased spontaneous motor activity. In all experiments, SPM appeared to have a powerful pharmacological activity compared with SPD. LD50 for SPD and SPM was 620 (500-769) mg/kg i.p. and 310 (200-480) mg/kg i.p., respectively.

Animals↗
PubMed1969

Role of the accompanying anion in the effect of calcium salts on potassium uptake by excised barley roots.

The effect of addition of Ca salts on accumulation of K from 5 mN KCl or K(2)SO(4) solutions was found to depend on whether Ca was added as Cl or SO(4) salt. Chloride as well as K uptake was increased when Ca and Cl concentrations in culture solutions were increased. Pre-treatment of roots with CaCl(2) stimulated subsequent K uptake from K(2)SO(4) solutions as compared to pre-treatment with distilled water but pre-treatment with CaSO(4) did not. The results indicate that addition of Ca salts to KCl or K(2)SO(4) solutions increased anion uptake and the effect of the addition of the Ca salts on K uptake was in part the result of increased anion uptake and not entirely a direct effect of Ca.In contrast, accumulation of Na and K from solutions containing these ions as SO(4) or Cl salts was changed from preferential uptake of Na to preferential uptake of K by addition of either CaCl(2) or CaSO(4). Thus, while Ca salts may influence K accumulation partly as a result of effects on anion uptake, the selectivity for K uptake depends on the presence of Ca and is influenced little by the accompanying anion.

Journal Article↗
PubMed1967

Genetical linkage relationships of DDT-resistance and Dieldrin-resistance in Culex pipiens fatigans Wiedemann.

The tropical house mosquito Culex fatigans readily develops resistance to DDT and to dieldrin and hexachlorocyclohexane. Studies of the mode of inheritance of these two types of resistance in material from Rangoon selected to a high resistance level showed DDT-resistance to be due to a single principal gene which was almost completely dominant and dieldrin-resistance to be due to a single gene allele neither dominant nor recessive, the hybrids being intermediate.The DDT-resistance factor was linked with the chromosome-2 marker genes y (yellow larva) and ru (ruby eye), at crossover distances of approximately 20 and 45 percentage units respectively. The dieldrin-resistance factor was linked with the chromosome-3 marker gene kps (clubbed palpi) with a crossover value between 35% and 40%. In contrast to Aedes aegypti, where these two genes are close together on chromosome 2, in Culex fatigans the dieldrin-resistance gene is separated on to chromosome 3.

Animals↗