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Biomedical subjects

N Takano

Publications and source records attributed to N Takano.

At least 91 records · Page 5Linked to original sources
PubMed1979

Pharmacological studies on a new thymoleptic antidepressant, 1-[3-(dimethylamino)propyl]-5-methyl-3-phenyl-1H-indazole (FS-32).

Some pharmacological actions of 1-[3-(dimethylamino)propyl]-5-methyl-3-phenyl-1H-indazole (FS-32), a newly synthesized indazole derivative, were investigated in comparison with imipramine. FS-32 showed anti-reserpine activity in a dose-dependent manner, whereas imipramine exhibited a bell-shaped dose-response pattern. Catecholaminergic potentiation was demonstrated with FS-32. The results obtained from a norepinephrine potentiation test in vitro suggest that FS-32 may act in a manner qualitatively different from the tricyclic antidepressant. FS-32 produced a definite suppressive effect on isolation-induced fighting without affecting coordinated motor activity and on the duration of afterdischarge elicited by electrical stimulation to the amygdala or the hippocampus without producing a slow wave pattern in the EEG. Similar effects on fighting behavior and the afterdischarge were shown under imipramine with a slight motor incoordination and with a slow wave pattern, respectively. FS-32 produced practically no peripheral anti-cholinergic action, while it antagonized central cholinergic activity. FS-32 tended to produce an increase in chatecholamine content in the brain without MAO or COMT inhibitory activity. Norepinephrine uptake was inhibited by FS-32, but less than by imipramine. These pharmacological properties suggest a potential clinical utility of FS-32 as an antidepressant possessing thymoleptic activities.

Acetylcholine↗
PubMed1977

Contribution of functional groups of 19-nor-progestogens to binding to progesterone and estradiol-17beta receptors in rabbit uterus.

The structural elements of 19-norprogestogens which may be essential for binding to progesterone and estradiol-17beta(E2) receptors were investigated in the rabbit uterine cytosol. The kinetic study showed that 19-nor-progestogens are competitive inhibitors of progesterone-receptor (8S) binding and E2-receptor binding. The affinities of steroids for the progesterone receptor were as follows: norethindrone (Ki of 2.3 X 10(-9)M) greater than 5alpha-dihydronorethindrone greater than norethindrone acetate greater than lynestrenol greater than 17alpha-ethynyl-estra-4-ene-3beta, 17beta-diol greater than ethynodiol diacetate (Ki of 1.3 X 10(-7) M). The affinities of steroids for the E2 receptor were as follows: ethynodiol diacetate (Ki of 1.3 X 10(-7)M) greater than 17alpha-ethynyl-estra-4-ene-3beta, 17beta-diol greater than norethindrone acetate greater than norethindrone greater than 5alpha-dihydronorethindrone greater than lynestrenol (Ki of 8.4 X 10(-7)M). The results indicate that 3-ketone and 17beta-hydroxyl groups, and the plane of ring A/B of 19-norprogestogen are important for binding to the progesterone receptor. The affinities of 19-nor-progestogens for the E2 receptor were very weak. Their affinities for the E2 receptor increased with addition of acetate or hydroxyl groups at the 3beta and 17beta positions, and were decreased by the elimination of a 3 oxygen function or the reduction of ring A.

Animals↗
PubMed1976

The oxygen-linked hydrogen ion binding (the Haldane coefficient) of bovine hemoglobin.

The Haldane coefficient (the amount of the oxygen-linked hydrogen ion binding of hemoglobin) was determined in bovine erythrolysate (Hb concentration equals 13.5 mM) by means of the differential titration method with varying PCO2 from 0 to 74 mm Hg and pH from 6.0 to 8.5 at 37 degrees C. The maximum value of the coefficient was found to be 0.49 mM per mM Hb at PCO2 equals 0 and pH 7.20. With increasing of PCO2, the coefficient became smaller in all ranges of pH studied. The coefficient under the conditions of pH 7.20 and PCO2 equals 45 mm Hg that are normally prevailing in the interior of bovine erythrocytes was 0.31.

Animals↗
PubMed1976

Effect of oxygen saturation on H+ and Cl- distribution across the red cell membrane in human and ruminant blood.

Alterations of red cell pH (pHc) and distribution ratios of H+ (gammaH+) and Cl (gammaCl-) between plasma and red blood cells with oxygenation of blood were studied in human blood (audult and fetal) and ruminant blood (bovine, goat and sheep). The experiments were carried out at a plasma pH of 7.0 to 7.7 and at 37 degrees C. In human blood pHc of fully oxygenated blood was 0.035 pH lower than that of fully deoxygenated blood in all ranges of plasma pH studied. In ruminant blood, however, the differences in pHc between oxygenated and deoxygenated blood were 0.011 in ox, and 0.003 in goat and sheep, all of them not being significant. The decreases in gammaH+ accompanying oxygenation were in fairly good agreement with those in gammaCl- in human blood and amounted to about 0.05. In ruminant blood, in spite of virtually zero changes in gammaH+ with oxygenation, the decreases in gammaCl- were slightly greater than those in human blood. There might be a species difference in the mechanisms of distribution of Cl- and H+ across the red cell membrane.

Animals↗
PubMed1975

Effect of an increase in cardiac output on the in vivo C02 titration curve of mixed venous blood.

The slope of the in vivo CO2 titration curve of blood (pH-[HCO3-]p relationship, in vivo slope, unit: slyke) expresses the buffering capacity of blood for CO2 in vivo or the buffering capacity of extracellular fluid for CO2. It depends on the extent of contributions by chemical and physiological buffering processes for CO2 occurring during CO2 titration. Theoretically, the in vivo slope obtained for mixed venous blood is independent of cardiac output during CO2 titration. The present study was attempted to confirm this theoretical concept experimentally. Anesthetized dogs were allowed to breathe air and then 10% CO2-25% 02 in N2 for 60 min for the titration in vivo. During the CO2 breathing period the legs were exercised through direct electrical stimulation of the muscles; this also induced an increase in cardiac output 130% above the air breathing period. The in vivo slope (delta[HCO3-]p/delta/pH-]p/"pH) of the mixed venous blood at an apparent steady state in the CO2 breathing period was 16 slyke, which was 5 slyke higher than in other dogs breathing CO2 at rest with a 60% increase in cardiac output observed in our previous study. This finding was discussed in relation to a greater contribution of tissue fluid for buffering of CO2. The present study suggests that cardiac output is a significant determinant of the buffering capacity of extracellular fluid.

Acid-Base Equilibrium↗
PubMed1972

Thiopeptin, a new feed-additive antibiotic: biological studies and field trials.

Thiopeptin is a new antibiotic, produced by Streptomyces tateyamensis and developed solely for animal use as a feed additive. The antibiotic content in animal tissue and feed was assayed in terms of the antimicrobial activity against Mycoplasma laidlawii A. This antibiotic was found to be relatively nontoxic in rats and mice. In chickens, this antibiotic is excreted into feces within 48 hr of administration and is not absorbed in tissue. It is well tolerated in both broilers and swine and is highly stable in animal feed. Thiopeptin-supplemented feed contributes to the improvement of weight gain, feed efficiency in chickens and swine, and the egg performance in layers. Thus, thiopeptin, when used as a feed additive, is quite suitable for supplementing animal nutrition.

Animal Feed↗