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B. C. Behera, Pune, India

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Auditory event-related potentials as indicators of good prognosis in coma of non-anoxic etiology
(2010-02-09T14:23:58Z) Jabbour, Rosette; Sawaya, Raja A.
The aim of this study is to evaluate whether auditory event-related potentials can predict the prognosis of recovery from coma resulting from different etiologies. The results of this study could then be used as an adjuvant test in helping the clinician evaluate patients in coma. We performed P300 auditory event-related potentials on 21 patients who developed a state of coma at our institution. We compared the results to the Glasgow coma scale at the onset of coma, on day 3, and day 21. We found that patients who developed coma secondary to cardiopulmonary arrest had no P300, and did not develop one, irrespective of their GCS, or their survival. Patients who developed coma from causes other than cardiopulmonary arrest who had a P300 at the onset of their coma, or developed one in the days that followed, ended up surviving their coma. On the other hand, patients in coma from non-cardiac causes who did not have, or developed a P300, did not survive their coma. We concluded that P300 had no prognostic value in coma secondary to anoxic brain injury, while it was an indicator of good prognosis if it was present in patients in coma from nonanoxic causes.
Searching for patterns of thermostability in proteins and defining the main features contributing to enzyme thermostability through screening, clustering, and decision tree algorithms
(2010-02-09T14:11:20Z) Ebrahimie, E.; Ebrahimi, M.; Ebrahimi, M.
Finding or making thermostable enzymes has been identified as an important goal in a number of different industries. Therefore, understanding the features involved in enzyme thermostability is crucial, and different approaches have been used to extract or manufacture thermostable enzymes. Herein we examined features that contribute to the thermostability of 2,946 proteins. We used various screening techniques (anomaly detection, feature selection), clustering methods (K-Means, TwoStep cluster), decision tree models (Classification and Regression Tree, CHAID, Exhaustive CHAID, QUEST, C5.0), and generalized rule induction (association) (GRI) models to search for patterns of thermostability and to find features that contribute to enzyme thermal stability. We found that Arg as the N-terminal amino acid was found solely in proteins working at temperatures higher than 70 ºC. Fifty-four protein features were shown to be important in feature selection modeling, and the number of peer groups with an anomaly index of 2.12 declined from 7 to 2 after being run using only important selected features; however, no changes were found in the numbers of groups when K-Means and TwoStep clustering modeling was performed on datasets with/without feature selection filtering. The depth of the trees generated by various decision tree models varied from 14 (in the C5.0 model with 10-fold cross-validation and with feature selection of the dataset) to 4 (in CHAID models) branches. The performance evaluation of the decision tree models tested here showed that C5.0 was the best and the Quest model was the worst. We did not find any significant difference in the percent of correctness, performance evaluation, and mean correctness of various decision tree models when feature selected datasets were used, but the number of peer groups in clustering models was reduced significantly (p<0.05) compared to datasets without feature selection. In all decision tree models, the frequency of Gln was the most important feature for decision tree rule sets; moreover, in all GRI association rules (100 rules), the frequency of Gln was used in antecedent to support the rules. The importance of Gln in protein thermostability is discussed in this paper.
Prediction of relative solvent accessibility using pace regression
(2010-02-09T14:07:18Z) Ghasem-Aghaee, Nasser; Meshkin, Alireza; Sadeghi, Mehdi
In this paper, a new approach for prediction of protein solvent accessibility is presented. The prediction of relative solvent accessibility gives helpful information for the prediction of native structure of a protein. Recent years several RSA prediction methods including those that generate real values and those that predict discrete states (buried vs. exposed) have been developed. We propose a novel method for real value prediction that aims at minimizing the prediction error when compared with existing methods. The proposed method is based on Pace Regression (PR) predictor. The improved prediction quality is a result of features of PSIBLAST profile and the PR method because pace regression is optimal when the number of coefficients tends to infinity. The experiment results on Manesh dataset show that the proposed method is an improvement in average prediction accuracy and training time.
TCRVß clonotypic analysis of vaginal T lymphocytes during experimental vaginal candidiasis in the murine system
(2010-02-09T14:06:09Z) Abu-Elteen, Khaled; El-Younis, Enas M.; Hamad, Mawieh; Yasin, Salem R.
To further understand the role of localized T cells in protection against vaginal candidiasis (VC), vaginal T lymphocyte TCRVβ repertoir was evaluated during experimental VC. RNA was extracted from lymphocytes of naïve and estrogen-treated Candida albicans-infected mice and RT-PCRed using TCRVβ primers corresponding to 24 common TCRVβ genes. All TCRVβ rearrangements were detected in vaginal T cells and thymocytes of naive mice. Although, the full complement of TCRVβ repertoire was detectable in vaginal T cells at days 14 and 21 post-infection, there was overrepresentation of TCRVβs 1, 6, 10 and 15 at day 14 and TCRVβs 1, 4, 6, 8.3, 10, 13, 14 and 18 at day 21. Expression of all TCRVβ rearrangements in vaginal T cells raises the possibility of an extrathymic developmental origin. Time-dependent overrepresentation of specific TCRVβs during VC may indicate infection-related specific T cell clonal expansion.
Identifying DNA splice sites using patterns statistical properties and fuzzy neural networks
(2010-02-09T13:36:25Z) Al-Daoud, Essam
This study introduces a new approach to recognize the boundaries between the parts of the DNA sequence retained after splicing and the parts of the DNA that are spliced out. The basic idea is to derive a new dataset from the original data to enhance the accuracy of the wellknown classification algorithms. The most accurate results are obtained by using a derived dataset that consists from the highest correlated features and the interesting statistical properties of the DNA sequences. On the other hand, using adaptive network based fuzzy inference system (ANFIS) with the derived dataset outperforms well-known classification algorithms. The classification rate that is achieved by using the new approach is 95.23 %, while the classification rates 92.12 %, 86.75 %, 83.13 % and 84.51 % are obtained by Levenberg- Marquardt, generalized regression neural networks, radial basis functions and learning vector quantization, respectively. Moreover, this approach can be used to represent the DNA splice sites problem in form if-then rules and hence provides an understanding about the properties of this problem.
A new member of Tau-class glutathione S-transferase from barley leaves
(2010-02-09T13:35:53Z) Mohabatkar, Hassan; Mohsenzadeh, Sasan; Saffari, Babak
Glutathione S-transferase is a family of multifunctional detoxification enzymes which are mainly cytosolic that detoxify natural and exogenous toxic compounds by conjugation with glutathione. Glutathione, an endogenous tripeptide, is important as either a reducing agent or a nucleophilic scavenger. This molecule alleviates the chemical toxicity in plants by reaction of glutathione S-transferase, and its conjugates can be transported to vacuole or apoplast. The plant soluble glutathione S-transferases grouped today into seven distinct Phi, Tau, Zeta, Theta, lambda, dehydroascorbate reductase, and tetrachlorohydroquinone dehalogenase classes. In this study, bioinformatics analysis of glutathione S-transferase gene in barley was carried out using Tau-class of barley glutathione S-transferase sequences in NCBI GenBank and isolated sequence. DNA extraction, primer design, PCR, electrophoresis, column purification, DNA sequencing and analysis by some software led to identify new sequences of Tauclass of glutathione S-transferase from barley, which is similar to Tau GST of the diploid wheat. Comparison of the deduced amino acid sequences of the three barley GST genes showed that they have 99 % identity with each other but only 45 % identity with the new GST. This sequence was submitted to NCBI GenBank with FI131240 accession number.
Hepatic and hematologic effects of fractions of Globimetula Braunii in normal albino rats
(2010-02-09T13:34:56Z) Kareem, G.K.; Ogbunugafor, H.A.; Okpuzor, J.
Globimetula braunii, a major medicinal plant used in traditional medicine in Nigeria, was evaluated for possible effects on hepatic and hematologic indices in Wister albino rats. The crude methanol extract of the plant was successively fractionated with hexane, chloroform, ethyl acetate, butanol and water. The MeOH extract of G. braunii and its fractions were administered to albino rats at a dose of 200 mg kg-1 body weight for 14 days. Assessments of liver function enzymes aspartate amino transferase (AST), alanine amino transaminase (ALT), as well as total and direct bilirubin levels were carried out. We observed significant increases (p≤0.05) in packed cell volume (PCV) and hemoglobin (Hb) in the rats treated with chloroform extract (CHCl3), ethyl acetate (EtOAc) and water (H2O) fractions. The red blood cell (RBC) count increased (p<0.05) after administration of CHCl3 and EtOAc fractions while white blood cell (WBC) count increased (p<0.05) in the crude and all its fractions except butanol. Significant decreases (p<0.05) in the activities of AST and ALT enzymes were observed in rats treated with chloroform fraction, while there was elevation in the activity of ALT in the butanol fraction group. There was no difference (p>0.05) in enzyme activities in the MeOH fraction. However, the administration of other fractions to the rats, led to increases (p<0.05) in the activities of both enzymes. Total and direct bilirubin showed increases (p<0.05) in EtOAc and hexane fractions while only direct bilirubin increased (p<0.05) in the crude fraction. The present study demonstrates that G. braunii chloroform fraction has an influence on hematologic functions and liver enzyme levels in rats.
Psidium guajava extract reduces trypanosomosis associated lipid peroxidation and raises glutathione concentrations in infected animals
(2010-02-09T13:33:23Z) Adeyemi, O.S.; Akanji, M.A.; Oguntoye, S.O.; Sulyman, F.
We have investigated the effects of the aqueous leaf extract of P. guajava on reduced glutathione (GSH) and alondialdehyde (MDA) concentrations in rats experimentally infected with Trypanosoma brucei brucei. The results obtained showed that the MDA concentrations in the serum and tissues of the infected animals were significantly increased (P<0.05) relative to the control (Table 2). However there was an insignificant difference in the GSH concentrations in the brain for the infected group and the infected but treated group relative to control (P>0.05) (Table 1). In contrast, a significant decrease (P<0.05) was observed for the GSH concentrations in the liver and kidney for the infected animals compared to the uninfected control and the infected but treated groups. The MDA concentrations in the serum and tissues of the infected but treated animals were significantly reduced when compared to the infected groups (P<0.05) (Table 2). In this study it was demonstrated that the aqueous extract was able to reduce the trypanosomosis associated lipid peroxidation as well as raise the level of GSH in the infected but treated animals significantly (P<0.05). We present evidence that the ability of the leaf extract of P. guajava to lower the MDA concentrations in the treatment group may be attributed to its antioxidant properties.
High doses of zinc and copper alter neither cerebral metal levels nor acetylcholinesterase activity of suckling rats
(2009-07-08T08:04:30Z) Bueno, Tania M.; Dressler, Valderi L.; Duarte, Fábio A.; Flores, Érico M. M.; Franciscato, Carina; Moraes-Silva, Lucélia; Pereira, Maria E.
This research investigated the in vivo (ZnCl2 27 mg/kg; CuSO4 10.2 mg/kg) and in vitro effects of zinc and copper on acetylcholinesterase activity of different cerebral areas, Zn and Cu levels in cerebrum, and body weight gain of young Wistar rats. Three-day-old rats were injected (s.c.) with 5 doses (saline, Zn, Cu or Zn+Cu) for 5 consecutive days and were killed 24 h after the last dose. In the other experiment, 7-day-old rats received only 1 dose (saline, Zn or Cu) and were killed at 1, 6 or 24 h after. For the in vitro experiments, the acetylcholinesterase activity from cerebrum of 8-day-old rats was analyzed in presence of Zn or Cu (0.01 to 1 mM). Regarding the in vivo experiments, only body weight gain was decreased by 5 simultaneous administrations of Zn and Cu. The acetylcholinesterase activity from cerebrum and cerebellum and cerebral zinc and copper contents were not altered by the treatments. In vitro, Cu 0.1 and 1 mM, but not Zn, inhibited the enzyme of both cerebrum and cerebellum. The enzymatic activity from cerebrum and cerebellum homogenate was more sensitive to Cu than the enzymatic activity from S2 and S1 fractions, respectively, since less metal was necessary to inhibit the enzyme.
Extract of Ulmus davidiana Planch barks induced apoptosis in human hepatoma cell line HepG2
(2009-07-08T07:27:52Z) Guo, Jia; Wang, Myeong-Hyeon
The cytotoxicity and mechanism of cell death induced by an extract of Ulmus davidiana Planch (UDP) were investigated. A 70 % ethanol extract of UDP exerted cytotoxic effects on HepG2 cells in a time- and dose-dependent manner caused a significant dose-dependent increase in the number of apoptotic cells. In addition, obvious shrinkage and destruction of the monolayer were observed in UDP-treated cells, but not in untreated cells. RT-PCR analysis revealed that the mRNA expression of p53 and c-myc was markedly increased in cells treated with the plant extract. In contrast, caspase-3 expression was induced after 1 h of incubation and then decreased at 3 h; however, it subsequently increased and remained at a relatively high level thereafter. Our data suggest the presence of a bioactive compound capable of killing liver carcinoma cells by apoptosis in a 70 % ethanol extract of UDP, and that the mechanism of apoptosis in the HepG2 cells included p53 and c-myc signaling.
Addition of contact number information can improve protein secondary structure prediction by neural networks
(2009-07-08T07:21:05Z) Lakizadeh, Amir; Marashi, Sayed-Amir
Prediction of protein secondary structures is one of the oldest problems in Bioinformatics. Although several different methods have been proposed to tackle this problem, none of these methods are perfect. Recently, it is proposed that addition of other structural information like accessible surface area of residues or prior information about protein structural class can significantly improve the prediction of secondary structures. In this work, we propose that contact number information can be considered as another useful source of information for improvement of secondary structure prediction. Since contact number, i. e. the number of other amino acid residues in the structural neighbourhood of a certain residue, depends on the secondary structure of the residue, we conjectured that contact number data can improve secondary structure prediction. We used two closely related neural networks to predict secondary structures. The only difference in the neural networks was that one of them was also provided with residue contact numbers as an additional input. Results suggested that addition of contact number information can result in a small, but significant improvement in prediction of secondary structures in proteins. Our results suggest that residue contact numbers can be used as a rich source of information for improvement of protein secondary structure prediction.
Instantaneous monitoring of hydroxyl radical-mediated protein alterations by green fluorescent protein
(2009-07-08T07:20:52Z) Isarankura-Na-Ayudhya, Chartchalerm; Prachayasittikul, Virapong; Seesai, Nanchaya; Thinjom, Sittichai
In the present study, green fluorescent protein (GFP) is successfully applied for instantaneous monitoring of hydroxyl radical-mediated protein alterations. Hydroxyl radical generated from metal-mediated Fenton’s reaction (in the presence of 50 μM copper ions, 10 mM ascorbic acid and 1.05 % hydrogen peroxide) rapidly suppressed the fluorescent emission of 60 % in a few seconds followed by a gradual decrease up to 75 % maximum inactivation was reached. The production of hydroxyl radical was experimentally proven to be specifically derived from copper-catalyzed Fenton’s reaction in which other divalent cations (e. g. Zn2+, Cd2+, Mn2+, Co2+ and Ni2+) exerted no inhibitory interaction. Supplementation of oxidative scavengers and metal chelators into the assay reaction provided protective effects on the fluorescent intensity. The degree of protection was in the order of EDTA > histidine >>> glutathione ~ sodium azide > thiourea ~ mannitol. The findings herein gain insights not only into the deleterious effect of reactive oxygen species on biological macromolecules but also the potential applicability as a versatile antioxidant screening assay.
Oreocnide integrifolia (Gaud.)Miq. exhibits hypoglycemic and hypolipidemic potentials on streptozotocin diabetic rats
(2009-07-08T07:20:38Z) Ansarullah; Devkar, Ranjitsinh; Jadeja, Ravirajsinh; Ramachandran, A. V.; Thounaojam, Menaka
Oreocnide integrifolia (Gaud.)Miq (Urticaceae) leaves are used to alleviate diabetic symptoms in folk medicine in northeast India. In the present study, dose and duration dependent hypoglycemic potentials were evaluated in streptozotocin induced diabetic rats. Administration of aqueous leaf extract (100, 250, 500 and 750 mg/kg body weight orally once daily) to diabetic rats reduced glycemic levels by 56 % by 4 weeks of treatment and was comparable to standard reference drug Metformin. The experimental data also revealed significant improvement in lowering lipid profile, Urea, Creatinine, Hb, HbA1c and insulin levels. The present study clearly demonstrates hypoglycemic and hypolipidemic potential of Oreocnide integrifolia leaf extract.
Activities of thiotetrahydropyridines as antioxidant and antimicrobial agents
(2009-07-08T07:20:26Z) Lawung, Ratana; Prachayasittikul, Supaluk; Prachayasittikul, Virapong; Ruchirawat, Somsak; Worachartcheewan, Apilak
Tetrahydropyridines have been reported previously as important medicinal agents. The present study, thiotetrahydropyridines were prepared and tested for antioxidants (DPPH and SOD assays) and antimicrobials (agar dilution method). The results show that 1-acetyl-1,2,3,4- and 1,2,3,6-thiotetrahydropyridines 15a-b, 16, 17 and 18a are new antioxidants that scavenge superoxide and free radicals. Whereas the analogs 15a and 16 are novel antimicrobials. Significantly, 1-acetyl-2-(1-adamantylthio)-3,4-diacetoxy-1,2,3,4-tetrahydropyridine (15a) is the most potent compound that inhibits the growth of Streptococcus pyogenes and Moraxella catarrhalis with MIC of 32 µg/mL, of Corynebacterium diphtheriae NCTC 10356 and of Vibrio cholerae (MIC of 64 µg/mL). Remarkably, the analog 15a is the most potent antioxidant and antimicrobial agent. This finding reveals a new and unique group of 1-acetyl-1,2,3,4-thiotetrahydropyridines as interesting lead compound with potential to be further developed for medicinal applications.
Novel activities of 1-adamantylthiopyridines as antibacterials, antimalarials and anticancers
(2009-07-08T07:20:08Z) Prachayasittikul, Supaluk; Prachayasittikul, Virapong; Ruchirawat, Somsak; Treeratanapiboon, Lertyot
To discover new bioactive lead compounds for medicinal purposes, herein, 2(1-adamantylthio)pyridine and derivatives (1-10) were prepared and tested for antibacterial (agar dilution method against 27 strains of microorganisms), antimalarial (against Plasmodium falciparum) and anticancer (MOLT-3, HepG2, HuCCA-1 and A549) activities. Results showed that all the tested derivatives selectively exerted antigrowth activity against Streptococci at 15-30 µg/mL. 3-Substituted (R) thiopyridines; 3 (R = NAc2), 5 (R = OH) and 6 (R = Br) exhibited antibacterials, antimalarials and anticancers. Significantly, 6-(1-adamantylthio) nicotinonitrile (10) is a promising antibacterial which selectively displays antigrowth activity against Vibrio cholerae, Vibrio parahaemolyticus, Edwardsiella tarda and beta-hemolytic Streptococcus group A with minimum inhibitory concentration of 30 µg/mL. The findings reveal that these 1-adamantylthiopyridines represent a novel class of antibacterial, antimalarial and anticancer agents with potential medicinal values.
Evaluation of consumer risk resulting from exposure against diphenylmethane-4,4'-diisocyanate (MDI) from polyurethane foam
(2009-03-11T10:25:08Z) Hoffmann, Hans-Dieter; Schupp, Thomas
Flexible polyurethane foam made from diphenylmethane-4,4’-diisocyanate (MDI) may contain a few ppm of residual monomer. As this foam is used in consumer articles like upholstered furniture and bed mattresses, the question arises if the residual monomer can result in consumer exposure and risk to consumer health. Integral skin polyurethane foam used for steering wheels and armrests and flexible polyurethane foam were analyzed for extractable MDI. The latter was also investigated with respect to migration and evaporation of MDI. There was no migration or evaporation of MDI detected. Against the experimental design and the corresponding detection limits less than 5.4 ng MDI per m³ air in the test chamber and a migration rate below 9 ng/cm² per day was found under simulated worst-case conditions (up to 10 ppm MDI in the flexible foam). For exposure by inhalation, these findings were compared to the German MAK value for MDI in air, the US EPA Reference Concentration and the NOAEC for respiratory tract irritation. For dermal exposure, the findings were compared against a derived No Expected Sensitization Induction Level (NESIL) for allergic contact dermatitis in man. As a result, polyurethanes containing up to 24 ppm extractable MDI do not pose a critical toxicological risk to consumers. Whether higher contents are acceptable depends on the result of migration and evaporation tests.
Effect of antibiotic therapy on the inflammatory responses during streptococcal pneumonia in emphysematous mice
(2009-03-11T10:24:47Z) Abe, Shuichi; Inoue, Sumito; Kubota, Isao; Nakamura, Hidenori; Sata, Makoto; Shibata, Yoko; Takabatake, Noriaki; Takeda, Hiroaki
Background and objective: Bacterial infection is one of the most important causes of acute exacerbation of respiratory failure in patients with chronic obstructive pulmonary disease (COPD). There were few studies evaluating the effects of early intervention by antibiotic on respiratory bacterial infection in COPD subjects. We investigated the effect of early intervention by respiratory quinolone antibiotic on the systemic inflammatory responses induced by streptococcal pneumonia using a mouse model of experimental emphysema. Methods: Experimental pulmonary emphysema was developed by a single intratracheal instillation of porcine pancreatic elastase in ICR mice. Three weeks later, lethal doses of Streptococcus pneumoniae were intratracheally inoculated, followed by oral administration of 50 mg/kg body weight of Grepafloxacin (GPFX) every day from a day after tracheal inoculation. Results: While all emphysematous mice without GPFX treatment died within 8 days, all emphysematous mice with GPFX treatment survived. Seventy two hrs after infection, serum levels of tumor necrosis factor alpha, chemokine (C-X-C motif) ligand 1, and CXCL2 (Macrophage inflammatory protein-2) in emphysematous mice with antibiotic therapy were significantly lower than those without therapy. Conclusions: Thus, the early intervention using a respiratory quinolone antibiotic prevents emphysematous mice with pneumonia from severe systemic inflammation, and rescues these mice from death. These results suggest that early intervention using a respiratory quinolone may improve the outcome of the exacerbated COPD patients.
Hepatoprotective effects of citric acid and aspartame on carbon tetrachloride-induced hepatic damage in rats
(2009-03-11T10:24:25Z) Abdel Salam, Omar M. E.; Shaffie, Nermeen M.; Sleem, Amany A.
The aim of this study was to investigate the effect of citric acid or the sweetening agent aspartame on the CCl4-induced hepatic injury in rats. Citric acid (10 mg/kg, 100 mg/kg or 1000 mg/kg), aspartame (0.625 or 1.25 mg/kg) or silymarin (25 mg/kg) was given once daily orally simultaneously with CCl4 and for one week thereafter. The administration of citric acid at 100 mg/kg or 1000 mg/kg to CCl4-treated rats reduced elevated plasma ALT by 44.1-63.3 %, AST by 47.8-70.6 %, ALP by 41.7-67.2 %, respectively compared to controls. Aspartame at 0.625 or 1.25 mg/kg reduced plasma ALT by 39.8-52.0 %, AST by 43.2-52.4 % and ALP by 50.0-68.5 %, respectively. Meanwhile, silymarin at 25 mg/kg reduced ALT, AST and ALP levels by 52.7, 62.2 and 64.7 %, respectively. On histology, citric acid at 1000 mg/kg resulted in near normalization of liver tissue. Vacuolar degeneration and necrosis were markedly reduced by 1.25 mg/kg aspartame. These results indicate that treatment with citric acid or the sweetening agent aspartame protects against hepatocellular necrosis induced by CCl4.
Beta-(1-adamantylthio)pyridine analogs as antimicrobials and antimalarials
(2009-03-11T10:24:01Z) Limnusont, Phattrapoom; Pingaew, Ratchanok; Prachayasittikul, Supaluk; Prachayasittikul, Virapong; Ruchirawat, Somsak
An array of interesting activities for bioactive 3-substituted thiopyridines have previously been reported. Herein, a series of α- and β-(1-adamantylthio) analogs of 3-picoline and phenylpyridines were prepared and investigated for antimicrobial (agar dilution method against 21 strains of microorganisms) and antimalarial (against P. falciparum) activities. It was found that β-thiopyridines, 5-(1-adamantylthio)-3-picoline (7) and 3-(1-adamantylthio)-4-phenylpyridine (8) are novel antimicrobials and antimalarials. Significantly, analogs 7 and 8 are very potent antimicrobials with MIC range of 2-32 µg/mL where 8 being the most potent. The β-sulfides 7 and 8 selectively inhibited the growth of tested gram-positive bacteria, but inactive against gram-negative bacilli including the members of Enterobacteriaceae. This study identified new antimicrobials that represent promising lead compounds suitable for fur-ther preclinical and clinical development.
Distribution of Abcg2 (BCRP) and Abcc2 (MRP2) mRNAs in rat small intestine and liver
(2009-02-04T15:42:31Z) Horibe, Sayo; Minegaki, Tetsuya; Ohnishi, Noriaki; Takara, Kohji; Yokoyama, Teruyoshi
The purpose of this study is to examine the distribution of Abcg2 and Abcc2 mRNAs in the intestine and liver of male Wistar rats, and any regional differences. Nine-week-old male rats were used, and their intestine divided equally into nine segments. The expression patterns of Abcg2 and Abcc2 mRNAs in the intestine and liver were examined using a reverse transcription-polymerase chain reaction (RT-PCR). PCR products for Abcg2 mRNA were readily detectable in the intestine, but no bands were detected in the liver. In addition, the level of Abcg2 mRNA increased significantly from the duodenum to ileum, indicating a regional difference in Abcg2 mRNA expression in the intestine. This regional difference was comparable to that of Abcb1/mdr1a as reported previously. On the other hand, Abcc2 mRNA was detected at a higher level in the liver than in the intestine. However, there was no regional difference in Abcc2 mRNA expression in the intestine. Collectively, Abcg2 was predominant in the intestine rather than liver in male Wistar rats, whereas Abcc2 was predominant in the liver. These findings will provide useful information for evaluating the gastrointestinal secretion of drugs as well as drug-drug interactions in rats.

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