YAKUGAKU ZASSHI
Online ISSN : 1347-5231
Print ISSN : 0031-6903
ISSN-L : 0031-6903
110 巻, 5 号
選択された号の論文の9件中1~9を表示しています
  • 根岸 和雄
    1990 年 110 巻 5 号 p. 293-303
    発行日: 1990/05/25
    公開日: 2008/05/30
    ジャーナル フリー
    N4-Aminocytidine is strongly mutagenic towards E. coli, S. typhimurium, B. subtilis and coliphages φX174 and M13mp2. It also causes mutations in mammalian cell lines and somatic cell mutations in D. melanogaster. The sequence analysis of deoxyribonucleic acid (DNA) from mutated phages revealed that N4-aminocytidine induces both adeninethymine (AT) to guanine-cytosine (GC) and GC to AT transitions. No transversions are detectable. When E. coli and the mammalian cells were cultured in the presence of [3H]-N4-aminocytidine, [3H]-N4-aminodeoxycytidine was found in their DNA. It is likely that N4-aminocytidine is metabolized within the cells into N4-aminodeoxycytidine 5'-triphosphate (dCamTP), which is then incorporated into DNA, thereby causing base-pair transitions. To prove this hypothesis, we studied the incorporation of dCamTP into polynucleotides in the in vitro DNA synthesis catalyzed by E. coli DNA polymerase I large fragment (Klenow enzyme) and DNA polymerase α from a mouse cell line. Both polymerases catalyze incorporation of dCamTP into DNA efficiently in place of dCTP opposite guanine, and less efficiently, but to a significant extent, in place of dTTP opposite adenine. These observations prove the erroneous nature of dCamTP as a substrate for DNA synthesis. DNA containing N4-aminocytosine was prepared by the incorporation of dCamTP into single-stranded phage DNA annealed to complementary oligonucleotides. The DNA was transfected to E. coli cells. The analysis of progeny phages indicates that N4-aminocytosine residue in DNA causes A to G or G to A mutation in the position opposite to the site where N4-aminocytosine should be incorporated.
  • 野村 靖幸
    1990 年 110 巻 5 号 p. 304-314
    発行日: 1990/05/25
    公開日: 2008/05/30
    ジャーナル フリー
    Xenopus oocytes have been used as an efficient and convenient expression system of messenger ribonucleic acid (mRNA) exogeneously injected. The transmembrane signalling mechanism of acetylcholine (ACh)- and serotonin (5-HT)-evoked inward current and properties of voltage-sensitive Ca channel (VSCC) current were studied using the oocytes injected with rat brain mRNA. M1 ACh or 5-HT1C receptor stimulation causes Cl- current via G-protein activation, inositol phosphate formation, an increase of free Ca2+ and finally gating of Cl channels via Ca2+-calmodulin. Protein kinase C seems to modulate the responses negatively. In addition, N type VSCC was also expressed and regulated by both protein kinases A and C. Limitations of the expression system as well as advantages are discussed.
  • 堀 一之, 佐武 紀子, 斎木 保久, 村上 孝夫
    1990 年 110 巻 5 号 p. 315-320
    発行日: 1990/05/25
    公開日: 2008/05/30
    ジャーナル フリー
    From the fronds of Diplazium nipponicum TAGAWA, an acylphloroglucinol glucoside'onioside (I)', has been isolated together with asiaticalin, astragalin, kaempferol-3-O-β-rutinoside and rutin. On the basis of chemical and spectroscopic evidence, the structure of I was elucidated as 1-(2-hydroxy-4, 6-dimethoxyphenyl)-3 (S)-hydroxybutane-1-one 3-O-β-D-glucopyranoside.
  • 指田 豊, 鈴木 一弘, 守屋 理, 小川 一紀, 下村 裕子, 原 昭二
    1990 年 110 巻 5 号 p. 321-324
    発行日: 1990/05/25
    公開日: 2008/05/30
    ジャーナル フリー
    A gasified-solvent-flow-extraction method has been developed for the microextraction of volatile constituents from powdered samples. A small amount (1-50 mg) of sample is inserted into a glass tube and heated to a preset temperature. The volatile constituents immediately vaporized by heat are transferred by a gasified solvent to a cooling tube where they are recovered as a solution. On this solution, gas chromatography analysis can be carried out directly without concentration and cleanup procedure. Liquid chromatography and thin layer chromatography can also be carried out on the solution. This method was applyed to the quantitative analysis of the volatile constituents of crude drugs. The optimization procedure for conducting this method is discussed.
  • 小松 節子, 遠藤 芳広, 鈴木 秋悦
    1990 年 110 巻 5 号 p. 325-331
    発行日: 1990/05/25
    公開日: 2008/05/30
    ジャーナル フリー
    The changes of protein phosphorylation were analyzed during mouse sperm capacitation and acrosome reaction. Sperm adenosine 3', 5'-cyclic monophosphate (cAMP) levels were gradually elevated during capacitation period. Although 82P uptake by sperm and protein phosphorylation increased during capacitation, the phosphorylation of a 45-kDa protein remained to be relatively constant. It was also demonstrated that acrosome reaction was induced by the treatment of capacitated sperm with 0.1 mM dibutyryl cAMP, 10 mM dibutyrylguanosine 3', 5'-cyclic monophosphate, 20 μM calcium ionophore A23187 or acid-solubilized zonae pellucidae. The phosphorylation of a 45-kDa protein was augmented during the acrosome reaction induced by such agents. These results suggest that changes in protein phosphorylation might be involved in the regulation of mouse sperm capacitation and acrosome reaction.
  • 藤原 博, 石田 説而, 島崎 義男, 内藤 誠之郎, 土谷 正和, 松浦 脩治
    1990 年 110 巻 5 号 p. 332-340
    発行日: 1990/05/25
    公開日: 2008/05/30
    ジャーナル フリー
    The amounts of endotoxin in commercial blood products were measured by the turbidimetric kinetic Limulus test with an ordinary reagent (LAL-HS) and a new endotoxinspecific reagent (LAL-ES). LAL-ES contains a sufficient amount of a water-soluble (1→3)-β-D-glucan derivative as a blocker of the (1→3)-β-D-glucan-mediated coagulation pathway in the reaction of the Limulus amebocyte lysate. The amounts of endotoxin in alubumin and globulin products measured with LAL-ES agreed with pyrogenic activities in rabbits, but those measured with LAL-HS did not. Added endotoxin in the blood products was well recovered with LAL-ES, but that in some products was excessively recovered with LAL-HS. The amounts of endotoxin in diphtheria-pertussis-tetanus combined vaccines measured with LAL-HS and LAL-ES agreed with the pyrogenic activities in rabbits. The results suggested the existence of a false-positive substance like β-glucan in the blood products but not in the vaccine. LAL-ES is more suitable for the detection of endotoxin in blood products than LAL-HS.
  • 森浦 俊次, 松田 秀秋, 久保 道徳
    1990 年 110 巻 5 号 p. 341-348
    発行日: 1990/05/25
    公開日: 2008/05/30
    ジャーナル フリー
    Effect of a 50% ethanolic extract ([M]) from dried whole body of Agkistrodon blomhoffii blomhoffii BOIE on a phagocytic activity of reticuloendothelial system was studied by the carbon clearance method in mice. The clearance-rate of carbon was significantly shortened 1 h after the oral administration of [M] (250 or 500 mg/kg, one time/d for 3d). [M] activated the phagocytosis of carbon by macrophage (Mφ) in the spleen and the phagocytosis of latex by peritoneal Mφ. These results suggested that [M] may promote the phagocytic activity on the reticuloendothelial system in mice and has a stimulatory effect on Mφ.
  • 喜多 敦子, 中村 秀雄, 門河 敏明, 丹 孝司
    1990 年 110 巻 5 号 p. 349-353
    発行日: 1990/05/25
    公開日: 2008/05/30
    ジャーナル フリー
    Analgesic activity of morphine administered rectally as a suppository was investigated in rats in order to ascertain analgesic activity of morphine suppository. Morphine hydrochloride given rectally as a suppository produced analgesic activity in a dose-related manner in the tail pressure and acetic acid-induced writhing tests, and its potency (ED50=about 17 and 0.689 mg/kg, respectively) was approximately twice that of morphine hydrochloride administered orally as an aqueous solution. The analgesic action was as durable as that of oral morphine, but its onset was faster. The plasma and brain levels of morphine reached peak until 30 min after rectal administration of morphine suppository, and these time-courses approximately corresponded with that of the analgesic action. These results suggest that morphine given rectally to rats as a suppository produces analgesic action equivalent or superior to orally administered morphine after absorption from the rectum.
  • 菊地 正雄, 佐藤 憲一, 白石 佳久, 中山 良一, 渡辺 玲子, 杉山 正尚
    1990 年 110 巻 5 号 p. 354-357
    発行日: 1990/05/25
    公開日: 2008/05/30
    ジャーナル フリー
    Mearnsitrin-3-O-α-L-rhamnoside, myricitrin, narcissin and other flavones were isolated together with phenolic carboxylic acids from the leaves of Berchemia racemosa SIEB. et ZUCC. From the wood of this plant, flavanones, flavanonols, phenolic carboxylic acids, (-)-catechin and others were isolated, and identified.
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