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The pancreatic tissues from patients with islet cell hyperplasia,insulinoma,and pancreatic adenocarcinoma,as well as normal pancreatic tissues were embedded with paraffin,serial sections were cut and mounted on glass slides.Immunohistochemical staining was carried out with N-myc down-stream regulated gene 2 (Ndrg2) monoclonal antibody by means of ABC method,and Western blotting was carried out to detect the expression and distribution of Ndrg2.The results showed that Ndrg2 positive immunoreactivity was mainly localized in the cytoplasm of islet cell,being similar to the localization of insulin positive immunoreactivity.The number and volume of pancreatic islets were increased in the patients with islet cell hyperplasia,and Ndrg2 expression was also increased.Western blotting results showed that the expression of Ndrg2 in the pancreas of patients with islet cell hyperplasia was increased compared with normal group.The above results suggest that Ndrg2 may play an important role in performing physiological function of islet cells.
ABSTRACT
Objective To investigate the mechanism of Chinese herbal medicine compound (Kaiyuqingwei Decoction) improving islet cells function of type 2 diabetes. Methods The models of type 2 diabetic rats were established by feeding with high-fat-diet and injecting low dosage of streptozotocin (15 mg/kg BW). Rats were randomly divided into model group, Kaiyuqingwei group, and Rosiglitazone group and normal control was established, at the same time, fasting and post-glucose loading 2 hours blood glucose, serum fructosamine and basal insulin were determined. Euglycemic hyperinsulin clamp technique was adopted to evaluate insulin sensitivity of periphery tissues, and intravenous glucose tolerance test to evaluate islets function. Adopting immunohistochemistry stain (EnVision) and computer image analysis technique to determine the expression of insulin, insulin receptor and insulin receptor substrate-1 in islets. Results There were insulin resistance, dysfunction of islet cells and obvious increase of blood glusose in model rats. All these could be improved by Kaiyuqingwei Decoction and Rosiglitazone. Meanwhile, immunohistochemistry stain of islets demonstrated that Kaiyuqingwei Decoction could increase expression of IRc and IRS-1. Conclusion Kaiyuqingwei Decoction have a certain positive role in improving glucose metabolism of type 2 diabetic rats. The mechanism include two aspects, one is elevation of insulin sensitivity, another is amelioration of dysfunction of islet cells. One of the important mechanisms of amelioration of dysfunction in islet cells is amelioration of insulin signal transduction in pancreatic islets.
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Objective To explore the relationship between TGF-?, P21ras, c-fos and the apoptosis of human embryonic pancreatic islet cells. Methods Semi-quantitative RT-PCR and immunohistochemistry (SABC method) were used to detect TGF-?, P21ras, c-fos expression at different growth periods of the primary human embryonic pancreatic islet cells and human fibroblast cells. Results P21ras expression was weak in every period of the pancreatic islet cells and significantly weaker than the fibroblast cells at exponential growth period and was stronger than in incubation period and retention period (P
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The aim of this study was to investigate the effect of a synthetic fifteen-residue peptide, Gly-Thr-Pro-Gly-Pro-Gln-Gly-Ile-Ala-Gly-Gln-Arg-Gly-Val-Val(P-15),on islet cell insulin secretion and insulin gene expression.Wistar rat islets,isolated by collagenase and trypsin digestion,were exposed to 0,0. 72,7.2,36?mol/L P-15 with 16.7mmol/L glucose.Insulin release increased approximately twofold in re- sponse to the concentration of 7.2?mol/L P-15 and Northern-blot analysis of islet mRNA with a rat pre- proinsulin cDNA probe showed a concomitant increase in mRNA level as compared with levels observed in islets treated with control.It is concluded that P-15 not only can stimulate the release of insulin but also in- crease the preproinsulin mRNA expression of islet cells.
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In this article, we report the pancreatic islet cells function of newborn pig pancreatic tissues cultured by Ham F_(10), and the condition of graft survived into the bodies of Sprague-Dawley rats, and also study the influence of Glycyrrhiza uralensis to the grafts. The cultured islet cells of newborn pig were transplanted into the mesenteric cavities (the first & second group), kidney cystic(the third group) and brain tissucs (the fourth group) of the 4 groups adult Sprague-Dawley rats. The first group rats drank Glycyrrhiza uralensis water, after 8～11weeks of operation a examination pathological was made with the cut graft The results showed that the first and second group grafts survived over 11weeks, and survived better the group drunk the Glycyrrhiza uralensis water was much better than other. The purpose of this experiment is to find the heteropolar source of pancreatic tissues offering body.
ABSTRACT
50 adult albino rats were divided randomly into 3 groups, i, e. partial hepatectomy group, sham-operation group and normal control group. Specimens of tail portion of pancreas were taken at 1, 2, 3, 6 and 14 days after operation respectively. Paraffin sections were made and stained with immunohistochemical PAP method to demonstrate insulin-containing B cells,C-peptide-containing B cells,glucagon-containing A cells and somatostatin-containing .D cells. The changes in hormone secretion activity of B, A and D cells have been observed during liver regeneration period. Based on the different amount of immunoreactive product, the endocrine activity of islet cells can be divided into 3 grades: +, ++, and +++. Percentage of each grade of islet cells was calculated and taken as the parameter of endocrine activity of islet cells. Insulin release activity of B cells increased after 1-3 days of operation, and insulin biosynthesis and/or storage enhanced 3-6 days after. Glucagon release activity of A cells raised gradually during 1-3 days after operation, and somatostatin released activity of D cells declined at the same time. After 6 days, endocrine activity of A cells returned to normal level, but release of somatostatin of D cells elevated. Endocrine activity of islet cells all recovered to normal level 14 days later. The changes of endocrine activity of B cells and A cells were closely related to and parallel with regeneration process of liver. The changes of D cells suggest that it probably be a reflection of regulation action on endocrine activities of B cells and A cells.