• Archives of Pharmacal Research
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• v.29 no.7
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• pp.605-616
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• 2006

A wide variety of drugs and endogenous bioactive amines are organic cations (OCs). Approximately 40% of all conventional drugs on the market are OCs. Thus, the transport of xenobiotics or endogenous OCs in the body has been a subject of considerable interest, since the discovery and cloning of a family of OC transporters, referred to as organic cation transporter (OCTs), and a new subfamily of OCTs, OCTNs, leading to the functional characterization of these transporters in various systems including oocytes and some cell lines. Organic cation transporters are critical in drug absorption, targeting, and disposition of a drug. In this review, the recent advances in the characterization of organic cation transporters and their distribution in the small intestine are discussed. The results of the in vitro transport studies of various OCs in the small intestine using techniques such as isolated brush-border membrane vesicles, Ussing chamber systems and Caco-2 cells are discussed, and in vivo knock-out animal studies are summarized. Such information is essential for predicting pharmacokinetics and pharmacodynamics and in the design and development of new cationic drugs. An understanding of the mechanisms that control the intestinal transport of OCs will clearly aid achieving desirable clinical outcomes.

• Journal of Acupuncture Research
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• v.15 no.2
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• pp.43-60
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• 1998

This study examined the histomorphomeric and histological changes of the left and right kidney in uninephrectomized rat. The results were as follows: 1. In the control, the right kidney was more prominent than the left in the basement membrane of glomerular capillaries. The podocyte had well developed Golgi apparatus in the left kidney and rough endoplasmic reticulum in the right kidney. 2. At the 30 days after unilateral nephrectomy, the basal lamina of glomerular capillaries was prominently thickened in the right kidney. The cytoplasm of the podocyte of the left kidney was markedly increased and had free ribosomes, developed Golgi apparatus and rough endoplasmic reticulum. 3. At the 30 days, the section of the glomeruli were more enlarged in the left kidney than in the right. 4. At the 20 day, the nuclear section of the podocytes were markedly enlarged in the right kidney, but those of the left kidney were diminished. The mitochondrial section of the podocytes were prominently increased in the right kidney. 5. The nuclear section of the parietal layer lining cells was no significant change in the right kidney. That of the left kidney was increased at the 20 days and decreased at the 40 days. The nuclear section of glomerular endothelium of the left kidney increased earlier than the right. 6. In the morphometry of the control kidney, the section areas, long and short diameters, the nuclear section, the mitochondrial section of the proximal tubule cells, and the changes of those were more large in the right kidney than in the left. 7. The luminal secretory vesicles and peroxisomes of the left kidney were more than the right at the 20 days. The increase of mitochodrial section in the proximal tubule cells of the left kidney was more prominent than the right. The large cytoplasmic vacuoles were more prominent in the left kidney than in the right. 8. The thickness of cytoplasm and brush border was more thick in the control left kidney than in the control right. The change of cytoplasmic thickness of the left kidney was increased earlier than in the right and both kineys were increased in the thickness of brush border at the 30 days.

• Animal cells and systems
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• v.7 no.4
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• pp.309-315
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• 2003

Renal dipeptidase (RDPase, membrane dipeptidase, dehydropeptidase 1, EC 3.4.13.19) has been widely studied since it was first purified from porcine kidney brush border membrane. It was reported that RDPase activity in urine samples of acute and chronic renal failure patients decreases. Nitric oxide (NO) is a highly reactive free radical involved in a number of physiological and pathological processes. NO is able to act in a dual mode, leading either to induction of apoptosis or to blunted execution of programmed cell death. NO inhibited the RDPase release from porcine renal proximal tubules, which could be blocked by L-NAME. Chitosan, the linear polymer of D-glucosamine in $\beta$(1\longrightarrow4) linkage, not only reversed the decreased RDPase release by NO but also increased NO production in the proximal tubule cells. The stimulatory effect of NO on RDPase release from proximal tubules in the presence of chitosan must be different from the previously proposed mechanism of RDPase release via NO signaling pathway. Chitosan stimulated the RDPase release in the proximal tubules and increased RDPase activity to 220% and 250% at 0.1% and 1%, respectively. RDPase release was decreased to about 40% in the injured proximal tubules and was recovered in proportion to the increase of chitosan. Chitosan may be useful in recovery of renal function from $HgCl_2$injury.

• Journal of Acupuncture Research
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• v.19 no.5
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• pp.199-208
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• 2002

Objective : This study was undertaken to determine if Carthami Semen Aquacupunc- ture(CSA) exerts protective effect against alterations in membrane transport function rabbits with mercury chloride(HG)-induced acute renal failure. Methods : The administration of Hg at a subcutaneous single dose of 10 mg/kg caused a reduction in GFR and an increase in fractional Na excretion, indicating generation of acute renal failure. When CSA were given for 7 days prior to Hg administration, such changes were significantly attenuated. The fractional excretion of glucose and phosphate was increased in rabbits treated with Hg alone. Results : The increase in rabbits treated with Hg following CSA are significantly lower than that in animals treated with Hg alone. Uptakes of glucose and phosphate in purified isolated brush-border membrane and Na-K-ATPase activity in microsomal fraction were inhibited in rabbits treated with Hg alone. Such changes were prevented by CSA. Uptakes of organic ions, PAH and TEA, in renal cortical slices were inhibited by the administration of Hg, which was prevented by CSA. Exposure of renal cortical slices to Hg in vitro caused an increased LDH release and lipid peroxidation, which was significantly prevented by CSA extract. Conclusions : These results indicate that the administration of Hg causes impairment in reabsorption of solutes in the proximal tubule via the generation of reactive oxygen species. CSA provides the protection against the impairment in proximal reabsorption, and its effect may be resulted from its antioxidant effect.

• BMB Reports
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• v.40 no.5
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• pp.783-790
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• 2007

Receptor binding plays an important role in determining host specificity of the Bacillus thuringiensis Cry $\delta$-endotoxins. Mutations in domains II and III have suggested the participation of certain residues in receptor recognition and insect specificity. In the present study, we expressed the cloned domain II-III fragment of Cry4Ba and examined its binding characteristics to mosquito-larval midgut proteins. The 43-kDa Cry4Ba-domain II-III protein over-expressed in Escherichia coli as inclusion bodies was only soluble when carbonate buffer, pH 10.0 was supplemented with 4M urea. After renaturation via stepwise dialysis and subsequent purification, the refolded domain II-III protein, which specifically reacts with anti Cry4Ba-domain III monoclonal antibody, predominantly exists as a $\beta$-sheet structure determined by circular dichroism spectroscopy. In vitro binding analysis to both histological midgut tissue sections and brush border membrane proteins prepared from susceptible Aedes aegypti mosquito-larvae revealed that the isolated Cry4Ba-domain II-III protein showed binding functionality comparable to the 65-kDa full-length active toxin. Altogether, the data present the 43-kDa Cry4Ba fragment comprising domains II and III that was produced in isolation was able to retain its receptor-binding characteristics to the target larval midgut proteins.

• The Journal of Internal Korean Medicine
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• v.21 no.2
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• pp.227-234
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• 2000

독성약물에 의한 급성신부전시 세뇨관세포의 물질 재흡수 장애에 대한 단삼(丹參) 추출액의 효과를 조사하였다. 토끼에 수은(HgCl2)을 10 mg/kg되게 피하 주사하여 급성신부전을 유발하였고, 단삼(丹參) 추출액의 효과는 수은을 주사하기 전 7일 동안 0.05% 액(液) 0.3 g/kg 용량을 경구 투여하여 관찰하였다. 수은을 주사하기 전 24시간 동안 요와 혈액을 채취하여 신장기능을 측정하여 대조기간(basal period)의 값으로 하였고, 수은을 주사한 후 24시간 동안 요와 혈액을 얻어 수은에 의한 신장기능 변화를 평가하였다. 수은을 처리한 후 사구체여과율이 대조값에 비해 감소하였고, 혈청내 creatinine 농도가 증가하였다. 이러한 결과들은 수은이 급성신부전을 유발하였음을 가리킨다. 수은을 처리한 동물에서 포도당 및 인산의 배설분율이 증가하였고, 이러한 변화는 brush-border membrane에서 물질의 이동장애와 Na-pump 활성의 감소에 기인하였다. 수은을 주사한 동물의 신장피질 절편에서 유기이온인 PAH와 TEA 이동이 억제되었다. 토끼의 신장조직에서 지질의 과산화가 수은을 주사한 후 증가하였다. 단삼(丹參) 추출액을 전 처리한 후 수은을 주사한 경우 수은에 의해 유발된 사구체여과율의 감소와 혈청내 creatinine 농도 증가 현상이 유의하게 완화되었다. 수은에 의한 세뇨관에서 물질의 재흡수 장애가 단삼(丹參) 추출액의 전처리에 의해 방지되었다. 단삼(丹參) 추출액은 수은에 의한 지질의 과산화를 억제하였다. 수은에 의한 급성신부전은 항산화제로 잘 알려진 DPPD에 의해 방지되었다. 이상의 결과를 종합하면 생체실험결과 수은에 의한 급성신부전의 유발과정에 지질의 과산화가 중요한 역할을 할 가능성을 보이고 있고, 단삼(丹參) 추출액은 수은에 의한 급성신부전을 방지하는 효과를 가지고 있으며, 그 효과는 단삼(丹參)의 항산화작용에 기인(起因)할 가능성이 많다.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.11
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• pp.1659-1664
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• 2008

To study the working mechanisms for non-starch polysaccharidases to improve the growth performance of broiler chickens, a 21-day feeding trial was conducted. Two dietary treatments were included: 1) wheat diet (the control); 2) wheat+xylanase diet (xylanase, Allzyme PT, Alltech, Kentucky, USA). There were 8 replicates with 8 birds each for each treatment and the experimental diets were given to birds from hatch. Feed intake and body weight were measured on days 7 and 21. At the same ages, samples were taken for the determination of selected groups of luminal and mucosa-associated bacteria, mucosal morphology, brush-border membrane (BBM) bound enzyme activity and ileal nutrient digestibility. The xylanase supplement increased (p<0.05) body weight gain (BWG) and improved feed conversion ratio (FCR) at the end of the experiment but protein and starch digestibilities were not affected (p>0.05) by xylanase. Up to day 7, xylanase increased the counts of C. perfringens in the ileum and total anaerobic bacteria (TAB) in the caeca (p<0.05, p=0.07, respectively). By day 21, the counts of ileal lactobacilli (p<0.05) and TAB (p=0.07) were lower in birds given the xylanase-supplemented diet than in those on the control diet. No significant differences were observed in the counts of mucosa-associated lactobacilli and coliforms between xylanase treatment and the control at both ages. Villus height at the jejunum was not affected (p>0.05) by the supplement but crypt depth at the same site was reduced at day 7. Also, xylanase tended to increase the concentration of BBM protein (p = 0.09) and the specific activity of sucrase (p = 0.07) at day 21.

• Applied Microscopy
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• v.35 no.3
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• pp.177-186
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• 2005

The foregut epithelium of the last instar larva in the scarab beetle, Allomyrina dichotoma was observed with electron microscopes. The foregut epithelium of the scarab beetle larva is composed of a single-layered squamous absorptive cell. The luminal surface of the epithelium is covered with cuticular intima. The free surface of the squamous cell has a irregular array of microvilli 'brush border', while cell membrans close to the basal lamina are infolded and a lot of mitochondria are concentrated in those processes. The cytoplasm in the epithelial cells is well developed nucleus, mitochondria. And the basal region of cell contains large lipid-, protein droplets and numerous glycogen granules. The basal lamina is located between the basal membrane and muscle bundle, providing barrier between the epithelium and the hemolymph. The epithelium is surround by the subepithelial space and muscles. The subepithelial space, which is composed of fibrous connective tissue is innervated by many tracheoles and axon.

• Journal of Microbiology and Biotechnology
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• v.21 no.9
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• pp.937-946
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• 2011

Several isolates of Bacillus thuringiensis (Bt) were screened for the vegetative insecticidal protein (Vip) effective against sap-sucking insect pests. Screening results were based on $LC_{50}$ values against cotton aphid (Aphis gossypii), one of the dangerous pests of various crop plants including cotton. Among the isolates, the Bt#BREF24 showed promising results, and upon purification the aphidicidal protein was recognized as a binary toxin. One of the components of this binary toxin was identified by peptide sequencing to be a homolog of Vip2A that has been reported previously in other Bacillus spp. Vip2 belongs to the binary toxin group Vip1-Vip2, and is responsible for the enzymatic activity; and Vip1 is the translocation and receptor binding protein. The two genes encoding the corresponding proteins of the binary toxin, designated as vip2Ae and vip1Ae, were cloned from the Bt#BREF24, sequenced, and heterologously expressed in Escherichia coli. Aphid feeding assay with the recombinant proteins confirmed that these proteins are indeed the two components of the binary toxins, and the presence of both partners is essential for the activity. Aphid specificity of the binary toxin was further verified by ligand blotting experiment, which identified an ~50 kDa receptor in the brush border membrane vesicles of the cotton aphids only, but not in the lepidopteran insects. Our finding holds a promise of its use in future as a candidate gene for developing transgenic crop plants tolerant against sap-sucking insect pests.

• Korean Journal of Acupuncture
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• v.23 no.1
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• pp.45-57
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• 2006

Objective : This study was undertaker to determine if Juglandis Semen herbal acupuncture (JSA) exerts protective effect against alterations in membrane transport function in rabbits with mercury-induced acute renal failure. Methods : Nephrotoxicity was induced by subcutaneous administration of Hg(a single dose of 10mg/kg) and JSA was performed at both sides of Shenshu($(BL_{23})$, Sinsu) for 7 days. Results: The administration of Hg at a subcutaneous single dose of 10 mg/kg caused a reduction in GFR to 12% of the basal value and an increase in fractional $Na^+$ excretion to 8.9-fold, indicating generation of acute renal failure. When JSA were given for 7 days prior to Hg administration, such changes were significantly attenuated. The fractional excretion of glucose and phosphate was increased to approximately 102- and 35-fold, respectively, in rabbits treated with Hg alone. The increase in rabbits treated with Hg following ISA are significantly lower than that in animals treated with Hg alone. Uptakes of glucose and phosphate in purified isolated brush-border membrane and $Na^+-K^+-ATPase$ activity in microsomal fraction were inhibited in rabbits treated with Hg alone, suggesting that impairment in proximal reabsorption of glucose and phosphate is resulted from a direct damage of membrane transport carriers and disruption of the normal $Na^+$ gradient. Such changes were prevented by JSA. Conclusion These results indicate that the administration of Hg causes impairment in reabsorption of solutes in the proximal tubule via the generation of reactive oxygen species. JSA provides the protection against the Hg-induced impairment in proximal reabsorption, and its effect may be resulted from its antioxidant action.