• 약학회지
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• 제38권6호
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• pp.637-645
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• 1994

The effect of various drugs on the stability of the liposomal membrane of phosphatidylcholine and cholesterol was studied, employing the fluorescence self-quenching method. Calcein was entrapped into the phospholipid small unilamellar vesicles and the leakage of the fluorescence probe was monitored on adding the drug to the system. The results of the experiments showed that phenothiazine derivatives, some potent local anesthetics and surface active agents were very effective in inducing the leakage of calcein from the liposome. The leakage-inducing activity of these drug substances has been ascribed to their surface activity and the perturbation of the liposomal membrane by these substances. On the other hand drug substance with low surface activity or without amphiphilic moieties did not show any effect or only small effect on the leakage of calcein from the liposomes. The effect of lipid concentration on the stability of the liposomes was also investigated to show that the higher concentrations of lipid more drug was required to induce the leakage. The effect of surface charges of vesicles was also studied, and the results showed that the charge on the liposomes enhanced the stability of the liposomes against the leakage-inducing activity of these drug substances.

• 약학회지
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• 제38권2호
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• pp.131-139
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• 1994

Calcein-encapsulated small unilamellar vesicles of various lipid composition were prepared using the sonication technique, and their stabilities at $20^{\circ}C$ were examined by measuring calcein leakage from the liposomes. The fluidity of these liposomal bilayers was also investigated by measuring the fluorescence polarization of DPH labelled into the liposomes. The results showed that liposomes made of PC mixtures with different acyl chain length were very stable, which may be due to the formation of interdigitated bilayer structure. The addition of cholesterol further stabilized these PC liposomes. However, addition of cholesterol reduced the encapsulation efficiences of liposomes. The fluidity of the liposomes was significantly decreased by cholesterol in the liquid crystalline state, but not changed in the gel state. These results suggest that the enhanced stability of PC mixture liposomes may be ascribed to the formation of stable interdigitated bilayer structure. In membrane-mimetic and drug-delivery studies, vesicles made of mixtures of various phospholipids are recommended instead of addition of cholesterol to the phospholipid.

• 한국식품과학회지
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• 제21권5호
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• pp.726-734
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• 1989

우유 지방구막의 고밀도 표피에 결합된 지질의 조성을 분석하기 위하여 지방구막의 고밀도 표피부분을 여러 농도의 비이온성 세제 Triton X-100으로 처리하였고 세제에 용해되지 않는 물질, 즉 지방과 결합된 성분을 분석하였다. 유지방구막의 단백질, 인지질, 콜레스테롤과 ganglioside의 양은 Triton X-100의 농도가 증가함에 따라 감소하였다. 불용성 표피물질로서 butyrophilin(band 12), xanthine oxidase (band 3)와 band 16이 SDS-polyacrylamide gel을 이용한 전기영동에서 나타났다. Phosphatidyl ethanolamine, phosphatidyl choline, phosphatidyl serine, phosphatidyl inositol 및 spingomyeline 함량은 처리되지 않은 원래의 막의 것과 큰 차이가 있어 표피물질의 주요 인지질로 규명되었다. 전체 지질에서 지방산은 myristate, palmitate, stearate(주요 포화지방산), oleate, linoleate(주요 불포화지방산)이었다. 단백질에 결합된 콜레스테롤은 다른 성분에서보다 단백질에 더 견고하게 부착되어 있었다. Ganglioside의 함량은 Triton X-100의 농도가 증가함에 따라 비례 감소하였다.

• 한국토양비료학회지
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• 제24권2호
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• pp.144-151
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• 1991

수도품종(水稻品種)의 내냉성관련인자(耐冷性關聯因子)로서 생체막구성물질(生體膜構成物質)에 중요(重要)한 역할(役割)을 하는 인지질(燐脂質)의 지방산조성(脂肪酸組成)과 지방산(脂肪酸)의 불포화비율(不飽和比率)을 증가(增加)시킬 수 있는 경화처리(硬化處理)에 의한 지방산(脂肪酸)의 변화(變化)를 조사(調査)하여 포장(圃場)에서 조사(調査)된 내냉성정도(耐冷性程度)와 비교검토(比較檢討)한 결과(結果)는 다음과 같다. 1. 수도(水稻) 32품종(品種)에서 분리(分離)한 인지질(燐脂質)의 지방조성(脂肪組成)은 Pamitic, Linoleic 및 Linolenic acid가 주(主) 지방산(脂肪酸)이었고, Palmitoleic, Stearic 및 Oleic acid가 소량(少量) 함유(含有)되어 있었다. 2. 저온처리(低溫處理)($15^{\circ}C$, 3일간)한 묘(苗)에서 포화지방산(飽和脂肪酸)인 Pamitic acid의 함량(含量)은 감소하고, 불포화지방산(不飽和脂肪酸)인 Linoleic acid의 함량(含量)은 증가하였다. 3. 지방산(脂肪酸)의 불포화비율(不飽和比率)은 저온처리(低溫處理)를 하므로써 높아졌으며, 내냉성(耐冷性)이 강(强)한 품종(品種)에서 비율(比率)이 높고, 약(弱)한 품종(品種)에서 낮아 내냉성정도(耐冷性程度)와 일치(一致)하는 경향을 보였다. 4. 경화처리(硬化處理)에 의하여 인지질지방산조성(燐脂質脂肪酸組成)중 Pamitic acid는 감소하고, Linoleic acid의 함량(含量)은 증가하였다. 5. 경화처리(硬化處理)를 하므로써 지방산(脂肪酸)의 불포화비율(不飽和比率)은 대조구(對照區)에 비하여 18~24% 증가되었다.

• 대한약리학회지
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• 제28권1호
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• pp.103-114
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• 1992

한국산 2년생 소의 신선한 대뇌피질로 부터 synaptosomal plasma membrane vesicles (SPMV)를 분리한 후 이 SPMV로 부터 추출한 총지질 (SPMVTL) 및 총인지질 (SPMVPL)로서 인공세포막을 제제하였다. SPMVTL 및 SPMVPL의 outer monolayer에 trinitrophenyl groups로 공유결합시킴으로써 형광 probe 1,6-diphenyl-1,3,5-hexatriene (DPH)의 outer monolayer 형광을 선택적으로 소광케한 후 SPMVTL 및 SPMVPL의 inner와 outer monolayer 사이의 비대칭적 유동성 존재 유무를 확인하였던 바 inner monolayer에 비하여 outer monolayer가 유동성이 크다는 것을 확인하였으며 SPMVTL에 비하여 SPMVPL의 유동성이 높았다. 뿐만 아니라 barbiturates는 SPMVTL의 유동성에 대하여는 유의성이 있을 만큼의 증감 효과를 나타내지 않았고 SPMVPL의 유동성은 감소시키되 주로 outer monolayer의 유동성을 감소시킨다는 것을 확인하였으며 barbiturates 종류에 따른 SPMVPL의 총유동성 감소의 크기는 pentobarbital > hexobarbital > amobarbital > phenobarbital의 순이었다.

• Archives of Pharmacal Research
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• 제20권1호
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• pp.1-6
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• 1997

We determined the microviscosity of synaptosomal plasma membrane vesicles (SPMV) isolated from bovine cerebral cortex and liposomes of total lipids (SPMTL) and phospholipids (SPMPL) extracted from SPMV. Changes in the microviscosity induced by the range and rate of lateral diffusion were measured by the intramolecular excimerization of 1, 3-di(1-pyrenyl)propane (Py-3-Py). The microviscosity values of the direct probe environment in SPMV, SPMTL and SPMPL were 38.17, 31.11 and 27.64 cP, respectively, at$37^{\circ}C$and the activation energies $(E_a)$ of the excimer formation of Py-3-Py in SPMV, SPMTL and SPMPL were 8.236, 7.448 amd 7.025 kcal/mol, respectively. Probe location was measured by polarity and polarizability parameters of the probe Py-3-Py and probe analogues, pyrene, 1-pyrenenonanol and 1-pyrenemethyl-3${\beta}$-hydroxy-22, 23-bisnor-5-cholenate (PMC), incorporated into membranes or solubilized in reference solvents. There existed a good linear relationship between the first absorption peak of the $^1_a$ band and the polarizability parameter $(n^{2}-1)/(2n^{2}+1)$.The calculated refractive index values for SPMV, SPMTL and SPMPL were close to 1.50, which is higher than that of liquid paraffin (n=l.475). The probe location was also determined by using a polarity parameter $(f-1/2f^{I})$. Here f=$({\varepsilon}-1)/(2{\varepsilon}+1)$ is the dielectric constant function and $f^I=(n^2-1)/(2n^2+1)$ is the refractive index function. A correlation existed between the monomer fluorescence intensity ratio and the solvent polarity parameter. The probes incorporated in SPMV, SPMTL, and SPMPL report a polarity value close to that of 1-hexanol $({\varepsilon}=13.29)$. In conclusion, Py-3-Py is located completely inside the membrane, not in the very hydrophobic core, but displaced toward the polar head groups of phospholipid molecules, e.g., central methylene region of aliphatic chains of phospholipid molecules.

• Journal of Ginseng Research
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• 제19권1호
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• pp.39-44
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• 1995

Total saponin from Korean red ginseng changed thermodynamic parameters of membranes from dipalmitoylphosphatidylcholine (DPPC) and ghost erythrocytes of human. In liposomes from DPPC, temperature of the main transition (Lb'-La) in liquid-crystalline phase increases by 0.2$^{\circ}C$ in average, but enthalpy does not change. Total saponin at a concentration of smaller than $10^5$% "stabilizes" the timid bilayers. At larger than 0.07 of saponin/DPPC ratio, saponin leads to an exclusion of the bound lipid molecules from the main phase transition into lamella liquid crystalline La-phase. Total saponin influences specifically all erythrocyte membrane transitions in a concentration-dependent manner, i.e. on the structures of all the main membrane skeleton proteins. A high structural specificity of saponin with membrane proteins, could be a base of specificity of physiological response of not only erythrocytes, but also other cells.her cells.

• Archives of Pharmacal Research
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• 제15권2호
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• pp.152-161
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• 1992

Selective quenching of 1, 6-diphenyl-1, 3, 5-hexatriene (DPH) by trinitrophenyl groups was utilized to examine the transbilayer fluidity asymmetry of model membranes of phospholipids (SPMVPL) extracted from synaptosomal plasma membrane vesicles (SPMV). The polarization (P), anisotropy (r), limiting anisotropy $(r_\infty$), and order parameter (S) of DPH in the inner monolayer were 0.019, 0.014, 0.018, and 0.047, respectively, greater than calculated for the outer monolayer of SPMVPL. Selective quenching of DPH by trinitrophenyl groups was also utilized to examine the effects of n-alkanols on the individual monolayer structure of SPMVPL. n-Alkanols fluidized the hydrocarbon region of bulk SPMVPL and the potencies of n-alkanols up to 1-nonanon increased with carbon chain length. It appears that the potencies in bilayer fluidization increase by 1 order of magnitude as the carbon chain length increases by two carbon atoms. The cut-off phenomenon was reached at 1-decanol, where further increase in hydrocarbon length resulted in a decrease in pharmacological activity. The n-alkanols had greater fluidizing effects on the outer monolayer as compared to the inner monolayer of SPMVPL, even though these selective effects tended to become weaker as the carbon chain length increased. Thus, it has been proven that n-alkanols exhibit selective rather than nonselective fludizing effects within transbilayer domains of SPMVPL.

• 한국수산과학회지
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• 제25권3호
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• pp.181-188
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• 1992

미역, 다시마 등 해조류의 주성분으로 알려진 알긴산(sodium alginate)을 0, 3, 6 및 $9\%$가 되도록 조제한 사료를 사용하여 Sprague-Dawley(SD) 웅성 흰쥐$(150\pm10g)$에 16주간 사육한 다음, 용량별 알긴산의 투여가 체중 변화와 간장의 세포막 성분으로서 미토콘드리아 및 마이크로솜 획분중의 과산화지질의 함량(malondialdehyde; n mole/mg protein) 및 과산화지표로서 peroxidizability index, 콜레스테롤과 인지질의 함량변화, 이에 따른 인지질 함량에 대한 콜레스테롤 함량의 비(Ch/Ph molar ratio), 그리고 간장의 세포막의 구성지방산 조성 등에 미치는 영향을 검토하여 몇 가지 유의성 있는 결과를 얻었다. 알긴산의 용량별$(0,\;3,\;6,\;9\%)$ 투여에 의한 체중 증가를 대조군의 136.5g을 $100\%$로 하여 비교하여 보면 3, 6 및 $9\%$의 알긴산 첨가군은 각각 $89.6\%,\;70.2\%,\;50.6\%$로 체중 증가가 유의성 있게 감소하고 있었다. 혈액과는 달리 미토콘드리아 및 마이크로 솜의 두 획분이 다같이 $6-9\%$의 알긴산 첨가군이 과산화지질의 함량을 아주 효과적으로 감소하고 있었으며, 과산화지표로서 peroxidizability index도 과산화지질의 함량과 거의 유사한 경향을 나타내고 있었다. 알긴산 무첨가의 대조군$(100\%)$ 대비 알긴산 첨가군$(3,\;6,\;9\%)$의 콜레스테롤의 함량을 비교하여 보면 미토콘드리아 획분에서는 각각$87.0\%\;, 77.5\%,\;72.3%$로, 그리고 마이크로솜 획분에서는 각각 $87.4\%\;, 68.0\%,\;68.1%$로 유의성 있게 감소하였으며, 인지질의 함량은 마이크로솜 획분에서만 $3-6\%$의 알긴산 첨가군이 유의성 있게 감소하였다. 따라서 인지질에 대한 콜레스테롤의 비(Ch/Ph molar ratio)는 두 획분에서 다같이 $3-6\%$의 알긴산 첨가군이 유의성 있게 감소하고 있음을 알 수 있었다. 총지방산의 함량은 알긴산의 첨가량에 따라 유의성 있게 감소하였고, 리놀산의 함량은 $3-6\%$의 알긴산 첨가군에서 유의성 있게 증가하였으며 (p<0.005), 리놀산에 대한 아리키돈산의 비(Ara/Lino ratio)는 $3-6\%$의 알긴산 첨가군에서 현저히 감소하였다. 따라서 이상의 데이타의 결과에서 본다면 알긴산의 투여가 노화과정에 있어서 생리적 변화를 효과적으로 조절할 수 있다는 사실을 암시하고 있었다.

• The Korean Journal of Physiology and Pharmacology
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• 제7권3호
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• pp.125-130
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• 2003

The aim of this study was to provide a basis for studying the molecular mechanism of pharmacological action of chlorhexidine digluconate. Fluorescence polarization of n-(9-anthroyloxy)stearic acid was used to examine the effect of chlorhexidine digluconate on differential rotational mobility of different positions of the number of membrane bilayer phospholipid carbon atoms. The six membrane components differed with respect to 2, 3, 6, 9, 12, and 16-(9-anthroyloxy)stearic acid (2-AS, 3-AS, 6-AS, 9-AS, 12-AS and 16-AP) probes, indicating different membrane fluidity. Chlorhexidine digluconate increased the rate of rotational mobility of hydrocarbon interior of the cultured Porphyromonas gingivalis outer membranes (OPG) in a dose-dependent manner, but decreased the mobility of surface region (membrane interface) of the OPG. Disordering or ordering effects of chlorhexidine digluconate on membrane lipids may be responsible for some, but not all of its bacteriostatic and bactericidal actions.