• The Korean Journal of Physiology and Pharmacology
• /
• 제5권3호
• /
• pp.231-241
• /
• 2001

The mammalian cortical collecting duct (CCD) plays a major role in regulating renal NaCl reabsorption, which is important in $Na^+$ and $Cl^-$ homeostasis. The M-1 cell line, derived from the mouse cortical collecting duct, has been used as a mammalian model of the study on the electrolytes transport in CCD. M-1 cells were grown on collagen-coated permeable support and short circuit current $(I_{sc})$ was measured. M-1 cells developed amiloride-sensitive current $5{\sim}7$ days after seeding. Apical and basolateral addition of ATP induced increase in $I_{sc}$ in M-1 cells, which was partly retained in $Na^+-free$ or $Cl^--free$ solution, indicating that ATP increased $Na^+$ absorption and $Cl^-$ secretion in M-1 cells. $Cl^-$ secretion was mediated by the activation of apical cystic fibrosis transmembrane regulator (CFTR) chloride channels and $Ca^{2+}-activated$ chloride channels, but $Na^+$ absorption was not mediated by activation of epithelal sodium channel (ENaC). ATP increased cAMP content in M-1 cells. The RT-PCR analysis demonstrated that M-1 cells express $P2Y_2,\;P2X_3\;and\;P2Y_4$ receptors. These results showed that ATP regulates $Na^+$ and $Cl^-$ transports via multiple P2 purinoceptors on the apical and basolateral membranes in M-1 cells.

• KSBB Journal
• /
• 제6권2호
• /
• pp.207-213
• /
• 1991

In this study poly (1-methyl-4-vinylpyridinium iodide-co-styrene) membrane with pyridinium cation as a fixed carrier was synthesized and the transport characteristics of the membrane was examined over various factors. As the concentration of the fixed carrier in the membrane was increased, the water content was increased. Meanwhile, the counter current of the organic anion and the chloride ion, the following results were obtained. Initial flux of Cl-, organic anion and Na+ decreased with the increasing thickness of membrane, and as the concentration of the fixed carrier increases, the initial flux of Cl- and organic anion increase but the initial flux of Na+ decreased. The flux equation of the organic anion, CCl3COO- was obtained from saturation kinetics as follows;$V_{o}=\frac{(8.67{\times}10^{-5}){\cdot}[NaCl]}{9.63{\times}10^{-2}+[NaCl]} mol/cm^2h$

• The Korean Journal of Physiology and Pharmacology
• /
• 제3권2호
• /
• pp.191-198
• /
• 1999

This study was undertaken to examine the effect of ethanol on $Na^+-dependent$ transport systems (glucose, phosphate, and dicarboxylate) in renal brush-border membrane vesicles (BBMV). Ethanol inhibited $Na^+-dependent$ uptakes of glucose, phosphate, and succinate in a dose-dependent manner, but not the uptakes of $Na^+-dependent.$ The $H^+/TEA$ antiport was reduced by 8% ethanol. Kinetic analysis showed that ethanol caused a decrease in $V_{max}$ of three transport systems, leaving $K_m$ values unchanged. Ethanol decreased phlorizin binding, which was closely correlated with the decrease in $V_{max}$ of $Na^+-glucose$ uptake. These results indicate that ethanol inhibits $Na^+-dependent$ uptakes of glucose, phosphate, and dicaboxylate and that the reduction in $V_{max}$ of $Na^+-glucose$ uptake is caused by a decrease in the number of active carrier proteins in the membrane.

• 대한환경공학회지
• /
• 제37권11호
• /
• pp.649-655
• /
• 2015

본 연구에서는 막 기반 수처리 기술의 핵심인 막 성능 및 특성을 혁신적으로 개선시키기 위한 새로운 형태의 막으로서 그래핀과 세라믹을 결합하는 세라믹 기반 그래핀 막(Ceramic-based graphene membrane (CbGM))을 만들고, 막에서 일어나는 물질 이동 특성을 파악하였다. 수투과 및 염 제거의 역할을 하는 활성층으로서 그래핀이 사용되었으며, 간단한 Filtration-assisted assembly (FAA) 방법을 도입하여 막을 합성하였다. 합성한 막의 표면 형태 및 특성 분석을 위해 주사전자 현미경 및 접촉각을 분석하였으며, 막 성능 및 특성 파악을 위해 3가지 용질(i.e., NaCl, $MgCl_2$, $Na_2SO_4$)을 회분식 정삼투 시스템에서 용질 이동을 측정하였다. 표면 형태 특성 분석과 물질 이동 결과를 통해, 그래핀 층의 두께 보다는, 활성층을 구성하는 그래핀 조각들 사이의 교합(Interlocking)이 막에 선택성 부여함에 있어서 가장 중요함을 확인하였다. 또한, 농도차를 구동력으로 하는 막 공정에 CbGM을 적용하였을 때, 수중의 음이온과 양이온의 최외각 전하비($Z^-/Z^+$)값이 증가할수록 용질 이동이 비례적으로 촉진되었으므로, CbGM의 표면이 양으로 하전되어 있으며, 이것이 전하된 물질의 이동에 매우 큰 영향을 끼친다는 것을 확인하였다.

• 대한약리학회:학술대회논문집
• /
• 대한약리학회 2006년도 The 6th Congress of the Federation of Asian and Oceanian Physiological Societies
• /
• pp.118.2-118.2
• /
• 2006

• Journal of Acupuncture Research
• /
• 제19권4호
• /
• pp.190-199
• /
• 2002

Objective : This study was performed to determine if Scutellaria balicalensis Georgi extract (SbGE) prevents oxidant-induced membrane transport dysfunction in renal tubular cells. Methods : Membrane transport function was estimated by measuring $Na^+$-dependent inorganic phosphate transport in opossum kidney (OK) cells. $H_2O_2$ inhibited phosphate transport in a dose-dependent manner. Results : The inhibitory effect of $H_2O_2$ was significantly prevented SbGE over concentration range of 0.005-0.05%. $H_2O_2$ caused ATP depletion, which was prevented by SbGE. $H_2O_2$ induced the loss of mitochondrial function as evidenced by decreased MTT reduction and its effect was prevented by SbGE. The $H_2O_2$-induced inhibition of phosphate transport was not affected by a potent antioxidant DPPD, but the inhibition was prevented by an iron chelator deferoxamine, suggesting that $H_2O_2$ inhibits $Na^+$-dependent phosphate transport via an iron-dependent nonperoxidative mechanism in renal tubular cells. Conclusion : These data suggest that SbGE may exert the protective effect against oxidant-induced membrane transport dysfunction by a mechanism similar to iron chelators in renal epithelial cells. However, furher studies should be carried out to find the active ingredient(s) of SbGE that exerts the protective effect.

• Journal of Pharmaceutical Investigation
• /
• 제24권3호spc1호
• /
• pp.49-57
• /
• 1994

The objective of this study was to determine whether Pz-peptide, an enhancer of hydrophilic solute permeability in the intestine, could elevate the paracellular permeability of the cornea and conjunctiva in the pigmented rabbit. The in vitro penetration of four hydrophilic solutes, mannitol (MW 182), fluorescein (MW 376), FD-4 (FITC-dextran, 4 KDa), and FD-10 (FITC-dextran, 10 KDa) across the pigmented rabbit cornea and conjunctiva was studied either in the presence or absence of 3 mM enhancers. Drug penetration was evaluated using the modified Ussing chamber. The conjunctiva was more permeable than the cornea to all four markers. EDTA and cytochalasin B showed higher effects on marker transport than Pz-peptide, but Pz-peptide elevated the corneal transport of mannitol, fluoresein, and FD-4 by 50%, 26%, and 50%, respectively, without affecting FD-10 transport. Possibly due to the leakier nature of the conjunctiva, 3 mM Pz-peptide elevated the transport of only FD-4 by about 45%, without affecting the transport of other markers. Furthermore, the transport of Pz-peptide itself across the cornea and conjunctiva increased with increasing concentration in the 1-5 mM range, suggesting that Pz-peptide enhanced its own permeability, possibly by elevating paracellular permeability. Effects of ion transport inhibitors on Pz-peptide transport were then investigated. PZ-peptide penetration was not changed by mucosal addition of $10\;{\mu}M$ amiloride or $10\;{\mu}M$ hexamethylene amiloride, inhibiting serosal $Na^{+}$ exit by $100\;{\mu}M$ ouabain, or replacing $Na^{+}$ with choline chloride in the mucosal side buffer. These results seggested that Pz-peptide enhanced the paracellular permeability of rabbit cornea and conjunctiva and further indicate that ion transporters were not involved in the Pz-peptide induced elevation of paracellular marker permeability.

• Applied Microscopy
• /
• 제19권2호
• /
• pp.119-137
• /
• 1989

Turtle bladder의 상피조직(上皮組織)과 세포막(細胞膜) 투과성(透過性)을 분석하기 위하여 동결절단법(凍結切斷法)을 적용(適用)하여 전자현미경(電子顯微鏡) 관찰을 하였으며 그 결과 다음과 같이 요약(要約)된다. 1. 방광상피(膀胱上皮)의 3가지 주요세포형(主要細胞形)은 granular-cell, ${\alpha}$ 및 ${\beta}$형(形)의 CA-rich cell로서 구분된다. 2. 과립성세포(顆粒性細胞)의 주요기능(主要機能)은 $Na^+$ 재흡수(再吸收)이며, 두 단계(段階)의 수송과정(輸送過程)으로 설명되며 정단세포막(頂端細胞膜)을 통한 $Na^+$의 세포내(細胞內) 확산이동(擴散移動)과 그후 기저막(基底膜)에 위치한 $Na^{+}\;-K^{+}$ 펌프에 의한 능동수송과정(能動輸送過程)이다. 3. ${\alpha}$ 및 ${\beta}$형(形) CA-rich cell은 $Na^+$ 수송(輸送)에 관여하지 않으며, ${\alpha}$형(形)의 CA-cell은 정단세포막(頂端細胞膜)의 proton펌프를 이용하여 proton 분필(分泌)에 관여한다. 또한 ${\beta}$형(形)의 CA-cell는 정단세포막(頂端細胞膜)을 통한 $HCO_{3}^-$ 분필수송(分泌輸送)의 기능을 가지고 있다. 4. 동결절단법(凍結切斷法)의 적용하에 세포막표면(細胞膜表面)의 특성(特性)을 관찰한 바, ${\alpha}$형(形)의 CA-cell의 정단세포막(頂端細胞膜)은 proton펌프를 함유하는 것으로 보이는 intramembrane particle이 다수 관찰되고 있으며, ${\beta}$형(形) CA-cell은 기저세포막(基底細胞膜)에서 이와같은 intramembrane particle이 나타나고 있다. 5. 상술(上述)한 두 type의 CA-cell에서 수송특성(輸送特性)의 차이는 proton 및 $HCO_{3}^-$ 분필수송(分泌輸送)이 서로 반대의 방향으로 일어나는 것으로 사료된다.

• The Korean Journal of Physiology and Pharmacology
• /
• 제3권5호
• /
• pp.513-519
• /
• 1999

Direct exposure of renal tubular brush-border membranes (BBM) to free cadmium (Cd) causes a reduction in phosphate (Pi) transport capacity. Biochemical mechanism of this reduction was investigated in the present study. Renal proximal tubular brush-border membrane vesicles (BBMV) were isolated from rabbit kidney outer cortex by Mg precipitation method. Vesicles were exposed to $50{\sim}200\;{\mu}M\;CdCl_2$ for 30 min, then the phosphate transporter activity was determined. The range of Cd concentration employed in this study was comparable to that of the unbound Cd documented in renal cortical tissues of Cd-exposed animals at the time of onset of renal dysfunction. The rate of sodium-dependent phosphate transport $(Na^+-Pi\;cotransport)$ by BBMV was determined by $^{32}P-Iabeled$ inorganic phosphate uptake, and the number of $Na^+-Pi$ cotransporters in the BBM was assessed by Pi-protectable $^{14}C-labeled$ phosphonoformic acid $([^{14}C]PFA)$ binding. The exposure of BBMV to Cd decreased the $Na^+-Pi$ cotransport activity in proportion to the Cd concentration in the preincubation medium, but it showed no apparent effect on the Pi-protectable PFA binding. These results indicate that an interaction of renal BBM with free Cd induces a reduction in $Na^+-Pi$ cotransport activity without altering the carrier density in the membrane. This, in turn, suggest that the suppression of phosphate transport capacity $(V_{max})$ observed in Cd-treated renal BBM is due to a reduction in $Na^+-Pi$ translocation by existing carriers, possibly by Cd-induced fall in membrane fluidity.

• 한국방사선학회논문지
• /
• 제11권2호
• /
• pp.157-165
• /
• 2017

본 논문에서는 고에너지 엑스선(6MeV)을 조사한 세포막 모델에서 $K^+-Na^+$ pump 시스템의 능동적 전달특성에 대하여 연구하였다. 이 실험에 사용된 세포막 모델은 $Na^+$슬폰화 폴리스티렌-디비닐벤젠(polystyrene-divinylbenzene) 혼성 중합막을 사용하였다. 이온의 초기플럭스는 $H^+$이온 농도의 증가와 함께 증가하였다. 이 실험의 조건을 pH 1.5-5, 온도 $36.5^{\circ}C$로 하여 첫 번째, 방사선이 조사되지 않은 막에서 $K^+$의 초기플럭스는 $2.09{\times}10^{-4}-1.32{\times}10^{-3}mole/cm^2{\cdot}h$이고 $Na^+$의 초기플럭스는 $7.09{\times}10^{-4}-1.09{\times}10^{-3}mole/cm^2{\cdot}h$으로 나타내었다. 두 번째, 방사선이 조사된 막에서 $K^+$의 초기플럭스는 $21.0{\times}10^{-4}-16.7{\times}10^{-3}mole/cm^2{\cdot}h$이고 $Na^+$의 초기플럭스는 $62.0{\times}10^{-4}-20.6{\times}10^{-3}mole/cm^2{\cdot}h$으로 나타내었다. 막의 $K^+/Na^+$선택도는 약 1.10이다. 조사된 막의 pH의 추진력은 조사되지 않은 막보다 약 9-20배 정도 유의성 있게 증가하였다. 세포막모델에서 $K^+-Na^+$의 pump 시스템의 능동적 전달특성이 비정상적이기 때문에 세포장해가 세포에서 발현된다고 사료된다.