Expression of ghrelin and its receptor GHS-R in the hypothalamus and gastrointestinal tract in rats with chronic renal failure / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the expression of ghrelin and its receptor, growth hormone secretagogue receptor (GHS-R), in the hypothalamus and gastrointestinal tract in rats with chronic renal failure (CRF) and explore their relationship with the disorder of gastrointestinal tract motility.</p><p><b>METHODS</b>SD rats were randomly divided into sham-operated group (n=8) and CRF group (n=16), and in the latter group, the rats were subjected to 5/6 nephrectomy to induce CRF. Real-time PCR and immunohistochemical staining were used to detect the distribution of mRNA and protein of ghrelin and GHS-R in the gastric fundus, duodenum, and hypothalamus.</p><p><b>RESULTS</b>The rats in the CRF group showed a significantly higher expression of ghrelin mRNA and protein in the gastric fundus but a lower expression in the hypothalamus than those in the sham-operated group (P<0.01), but the expression in the duodenum was similar between the two groups (P>0.05). The expression of GHS-R mRNA and protein in the gastric fundus was significantly higher in the CRF group than in the sham-operated group (P<0.01), while in the hypothalamus and duodenum, the expression was significantly lower in the CRF group (P<0.01).</p><p><b>CONCLUSION</b>The different distribution patterns of ghrelin and GHS-R in the tissues may be an important pathological basis of gastrointestinal motility disorder in CRF.</p>

Construction and expression of recombinant adenovirus containing human catalase gene in vitro / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To construct the adenovirus vector containing recombinant human catalase (CAT) and to express the recombinant gene in vitro.</p><p><b>METHODS</b>Total RNA was extracted from human leukocytes and full-length human CAT cDNA was obtained with RT-PCR method. The CAT gene was cloned into pcDNA3.1(+) vector and pcDNA3.1(+)CAT was constructed. The positive clones were confirmed by the restriction enzyme digestion and gene sequencing. The CAT gene was cloned into the entry vector pENTR1A, and pENTR1A-CAT vector was constructed. By LR reaction pENTR1A-CAT and pAd/CMV/V5-DEST was recombined in vitro, and the recombinant adenovirus pAd/CMV/V5-DEST-CAT was obtained. The positive pAd/CMV/V5-DEST-CAT was confirmed by sequencing and transfected into 293A cells with Pac I linearization and Lipofectamine 2 000, and the recombinant virus particles were packaged and amplified in the cells. The expression of CAT protein and CAT enzyme activities of the recombinant virus were determined by Western blot and 240 nm UV absorption methods.</p><p><b>RESULT</b>High expression of recombinant adenovirus was obtained and the expressed human catalase had high enzyme activity.</p><p><b>CONCLUSION</b>Ad/CMV/V5-DEST-CAT vector containing human catalase gene has been constructed successfully; and the expressed enzyme in 293A cells has high activity.</p>

Expression of protein arginine N-methyltransferases in E3 rat models of acute asthma / 南方医科大学学报

<p><b>OBJECTIVE</b>To observe the expression of protein arginine N-methyltransferase (PRMT) genes in the lung and spleen of E3 rats with acute asthma.</p><p><b>METHODS</b>E3 rats with ovalbumin-induced pulmonary inflammation were divided into two groups (n=10), and the validity of the acute asthma model was evaluated by histological observation with HE and PAS staining and by measurement of NO production. Semi-quantitative RT-PCR was employed to detect the expressions of PRMT1-PRMT6 genes in the lung and spleen tissues of the rats.</p><p><b>RESULTS</b>In the lung tissue of the asthmatic rats, the gene expressions of PRMT1 (P<0.01), PRMT2 (P<0.01), PRMT3 (P<0.05) and PRMT5 (P<0.05) were significantly increased, but the expression of PRMT4 gene (P<0.05) was significantly decreased as compared with those in the control tissue. In the spleen tissue of the asthmatic rats, the expressions of PRMT2 (P<0.05) and PRMT5 genes (P<0.05) showed a significant increase as compared with those in the control rat tissue.</p><p><b>CONCLUSION</b>The gene expressions of PRMTs vary significantly between asthmatic rats and control rats, suggesting that PRMTs play an important role in the post-translational modification process of asthma-related genes.</p>

Identification of differentially expressed genes in rat asthma model by suppression subtractive hybridization technology / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To identify differentially expressed genes related to asthma by using a rat model.</p><p><b>METHODS</b>Total RNA extracted from the asthmatic rats was taken as the tester and the total RNA from the control rats as the driver. Suppression subtractive hybridization (SSH) was used to isolate the cDNA fragments of differentially expressed genes. The products of SSH were inserted into pGEM-T Easy vector to establish the subtractive library. The library was amplified through E.coli transformation and positive clones of the transformants were screened. The white clones in selective medium from cDNA library were isolated and digested by EcoR I restriction endonuclease. Thirty-six positive clones were chosen randomly and sequenced. Nucleic acid similarity was subsequently analyzed by comparing with the data from GenBank (NCBI).</p><p><b>RESULTS</b>There were more than 300 white clones in the cDNA library. The clones were sequenced and similarity search (http://www.ncbi.hlm.nih.gov/BLAST) revealed 4 known genes, 2 ESTs without homologous genes and 3 potential new gene fragments.</p><p><b>CONCLUSION</b>The forward-subtracted cDNA library for differentially expressed in the lung of asthmatic rats has been successfully constructed and the interesting candidate genes related to asthma have been identified.</p>

KCNE2 protein S98 phosphorylation in heart of old SHR rats detected by point mutagenesis / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the phosphorylation of KCNE2 protein in heart of old SHR rats.</p><p><b>METHODS</b>The membrane proteins from ventricular myocardium of old SHR were extracted, treated with or without alkaline phosphatase and tested binding with Ab2 (an anti-KCNE2 polyclonal antibody) by Western blot. A KCNE2 fusion protein with c-myc was obtained from in vitro translation system and treated with or without alkaline phosphatase. A series of mono- and double-point mutated fusion KCNE2 proteins with c-myc were obtained from an in vitro translation system, and Western blots with Ab2 or anti-myc antibody were performed.</p><p><b>RESULTS</b>After alkaline phosphatase treatment, Ab2 significantly attenuated its binding with KCNE2. In vitro translation system confirmed that after alkaline phosphatase treatment, Ab2 weakened binding ability to KCNE2 while binding to c-myc was not changed. Point mutation experiments showed that serine residue in position 98 of KCNE2 proteins might be phosphorylated.</p><p><b>CONCLUSION</b>KCNE2 protein in heart of old SHR rats is phosphorylated and this phosphorylation takes place in serine residue of position 98.</p>

A method with TRIzol~ reagent and liquid nitrogen to extract high-quality RNA from rat pancreas / 西安交通大学学报(医学版)

Objective To establish a quick,economical and reproducible method for high-quality RNA extraction from pancreas.Methods We utilized TRIzol Reagent and liquid nitrogen to isolate total RNA from the rat pancreas.The RNA quality was determined by detection of its content and optic density(A) at 260/280nm,and electrophoresis in 1% non-denatured agarose gel.Then reverse transcription-polymerase chain reaction(RT-PCR) was performed to detect expression of the pancreas-specific genes.Results The content of the total RNA extracted from the rat pancreas reached 3-6?g/mg pancreatic tissues,and A260/280 ratio was 1.75-1.89.Electrophoresis of the total RNA showed 28S and 18S rRNA bands with clear smear between them.The RT-PCR products of pancreas-specific genes including insulin 1,glucagon,?-amylase and housekeeping gene ?-actin all exhibited clear bands on 1% agarose gel,which were located in the expected positions,respectively.Conclusion These results suggest that we have successfully isolated the high-quality and intact RNA from the rat pancreas with TRIzol Reagent and liquid nitrogen.The extracted total RNA can be used in RT-PCR for pancreatic gene expression.