巻号一覧
12 巻, 4 号
選択された号の論文の7件中1～7を表示しています
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谷口 直之, 近藤 宇史, 石川 智久1987 年 12 巻 4 号 p. 180-190
発行日: 1987/07/01
公開日: 2011/03/04
ジャーナル フリーThis paper reviews studies on a) biosynthesis and degradation of glutathione, b) regulation of glutathione levels, and c) transport of glutathione. Glutathione levels in tissues and cells are regulated by a feed back inhibition of γ-glutamyl cysteine synthetase by GSH. Glutathione is conjugated with numerous electrophiles by a catalytic reaction of glutathione S-transferase and the reaction product, glutathione S-conjugate also plays an important role in the regulation of glutathione levels. The S-conjugate releases the feed back inhibition of γ-glutamyl cysteine synthetase by GSH. The S-conjugate also inhibits glutathione reductase and this brings about changes in GSH/GSSG ratio. GSSG efflux occurs in two different processes such as high affinity (low Km) and low affinity (high Km) processes. The glutathione S-conjugate competes the low affinity process, indicating that GSSG and glutathione S-conjugate are transported by the same carrier system. These processes are energy-dependent and requires ATP. The GSSG efflux is inhibited by NaF. The GSSG-stimulated ATPase is present in erythrocytes, heart muscle as well as canalicular or basolateral membranes of the liver. Investigation on efflux of GSSG and glutathione S-conjugate indicates that a transport mechanism analogous to that of erythrocytes exists in various cells and tissues. The efflux of these materials is considered to be an extracellular parameter to assess oxidative stress in cells and tissues.抄録全体を表示PDF形式でダウンロード (1440K) -
竹縄 忠臣1987 年 12 巻 4 号 p. 191-199
発行日: 1987/07/01
公開日: 2011/03/04
ジャーナル フリーInositol phospholipids hydrolysis is coupled to receptor activation involved in the elevation of intracellular Ca2+and protein kinase C. Recently, this signal transduction system has been paid attention, since this system mediates not only hormonal effects but also cell growth. cell transformation and differentiaton.
In this signal transduction system, guanine nucleotide binding protein.makes important roles in the hydrolysis of inositol phospholipids through lowering Ca2+ for phospholipase C activation. The hydrolysis of phosphatidylinositol 4, 5-bisphoshpate to inositol 1.4, 5-trisphosphate (IP3) and diacylglycerol (DG) produces two important second messengers. IP3 can release Ca2+ from intracellular Ca2+ store and DG can activate protein kinase C. Therefore, this signal transduction system activates two kinases, Ca2+/calmodulin kinase and protein kinase C, which leads to various cellular responses.抄録全体を表示PDF形式でダウンロード (1168K) -
竹中 亨1987 年 12 巻 4 号 p. 201-210
発行日: 1987/07/01
公開日: 2011/03/04
ジャーナル フリーRecent studies on infrared and Raman spectra of monolayers, bilayers, and Langmuir-Blodgett (LB) films are reviewed. Regarding infrared measurements of these films, the transmission, attenuated total reflection (ATR), reflection-absorption (R-A), and surface electromagnetic wave (SEW) techniques are outlined. For Raman measurements, on the other hand, the external reflection, optical waveguide, and total internal reflection techniques are briefly described. The advancement of these techniques and the improvement in sensitivity of infrared and Raman spectrophotometers allowed us to study the structure and molecular orientation even in single monolayers at various interfaces.
The infrared ATR spectroscopy of stearic acid LB films indicates that there exists the structural and orientational heterogenity among the first few monolayers. The R-A spectroscopy of cadmium arachidate LB films suggests the almost perpendicular orientation of the molecular axis on the silver substrate as well as significant disruption of molecular conformation and lateral packing during heating and melting processes. Application, of the total internal reflection spectroscopy to the study on resonance Raman spectra of spread monolayers on water and of adsorbed monolayers at an oil-water interface indicates changes in molecular orientation and interaction with changes in the amount of molecules in the monolayers.抄録全体を表示PDF形式でダウンロード (1341K) -
Donnan電位と表面電位大島 広行1987 年 12 巻 4 号 p. 213-219
発行日: 1987/07/01
公開日: 2011/03/04
ジャーナル フリーA novel model for the potential distribution across a membrane surface in an electrolyte solution proposed recently by us is reviewed with particular emphasis on the role of the Donnan potential. This model assumes that a membrane has a surface layer in which charged groups are distributed and that the electrolyte ions can penetrate the surface charge layer. Electrophosesis problems, effects of nonuniform charge distribution in the surface layer, and the electrostatic interaction of membranes with surface charge layers are discussed along the line of the present model.抄録全体を表示PDF形式でダウンロード (590K) -
アミノ酸輸送吉川 正和, 岸田 昌浩, 谷垣 昌敬, 江口 彌1987 年 12 巻 4 号 p. 221-222
発行日: 1987/07/01
公開日: 2011/03/04
ジャーナル フリーPDF形式でダウンロード (210K) -
宮本 学, 中張 隆司, 吉田 秀世, 今井 雄介1987 年 12 巻 4 号 p. 223-230
発行日: 1987/07/01
公開日: 2011/03/04
ジャーナル フリーElectro-osmotic flow and streaming potential were demonstrated in frog skin and gastric mucosa by the oscillating method (Imai, et al 1986) in a Ussing chamber1, 2) . Electro-osmotic flow was monitored directly using a photodiode. The flow increased in proportion to the amplitude of the applied rectangular electropotential wave. Their ratios were 0.31μl/min/V /cm2 for the skin and 0.69, μl/min/V/cm2 for the gastric mucosa. In pH 7.4 Ringer solution, skin behaved as a cation exchanger and gastric mucosa as an anion exchanger. The electro-osmotic flow evoked by the potential oscillation was also measured against a constant osmotic flow induced by a sucrose gradient. The electric potential which balanced the finite osmotic flow was-241 mV /200 mOsm for the skin and 156 mV /100 mOsm for the gastric mucosa. The parameters of the theoretical model were also determined using the network thermodynamics. The values of the reflection coefficients (σCl-σNa) and hydraulic conductivities (Lp) were 0.14, 2 × 10-7 cm/sec/atm for the skin, and-0. 11, 4.5 × 10-7 cm/sec/atm for the gastric mucosa. The absolute values of reflection coefficients of each ion for the skin were σCl= 0.96 and σNa = 0.82.抄録全体を表示PDF形式でダウンロード (845K) -
飯山 悟, 都甲 潔, 山藤 馨1987 年 12 巻 4 号 p. 231-237
発行日: 1987/07/01
公開日: 2011/03/04
ジャーナル フリーThe effect of taste stimulants on a DOPH (dioleyl phosphate) Millipore membrane was investigated as a model system of taste reception. Quinine, HCl, NaCl and sucrose were chosen as bitter, sour, salty and sweet substances, respectively. From the measurements of membrane potential and membrane resistance, it is conceivable that quinine, HCl and NaCl affect a phase boundary potential while sucrose affects a diffusion potential. Dynamic profiles of membrane potential also suggested that HCl and NaCl acted at the surface of membrane, but quinine and sucrose penetrated into the membrane. The intensity of their action on an electric potential was associated qualitatively with the threshold values of taste reception in man. Most of the results found in this model membrane may be realized for a living system. On the difference of taste quality between sour and salty substances, some discussions were added.抄録全体を表示PDF形式でダウンロード (883K)
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