This study was designed to investigate the effect of cholestyramine on the formation of pigment gallstones in high carbohydrate diet-fed hamsters and whether that effect occurred because of cholecystokinin action. Forty seven hamsters were divided into three groups: group I(n = 16) was fed on normal rodent chow(43% carbohydrate), group II(n = 14) was fed on a high CHO diet(65% carbohydrate), group III(n = 17) was fed on a high CHO diet containing 4% cholestyramine. Gallstones developed in 0% of group I, 42.9% of group II and 5.9% of group III(P< 0.05, group II vs III). To evaluate the chronic status of cholecystokinin level, the wet weight of pancreas and the average area of pancreatic acinar in microscopic high power field were measured. There was no significant difference between group II and group III in pancreatic weight and average area of pancreatic acinar(P> 0.05). In gallbladder bile analysis, there was also no significant difference between group II and group III in cholesterol, phospholipid, total calcium, total bilirubin and bile acid levels. In conclusion, cholestyramine decreases the frequency of pigment gallstone formation in high CHO diet-fed hamsters, but it is not clear whether the mechanism of cholestyramine decreasing the gallstone formation is due to the action of cholecystokinin.
Animal ; Bilirubin/metabolism ; Cholecystokinin/*analysis ; Cholelithiasis/*pathology ; Cholesterol/metabolism ; Cholestyramine/*administration & dosage ; Dietary Carbohydrates/*administration & dosage ; Female ; Gallbladder/*metabolism/pathology ; Hamsters ; Male ; Mesocricetus ; Organ Weight ; Pancreas/physiopathology ; Phospholipids/metabolism ; Pigmentation ; Support, Non-U.S. Gov't

We investigated the induction of resistance to Clonorchis sinensis infection by prior infection in rat and hamster models. Animals were challenged with C. sinensis metacercariae, then treated with praziquantel and reinfected. Worm recovery rate in reinfected animals was used to estimate resistance to reinfection. The determined resistance rates to reinfection in rats and hamsters were 97.7% and 10.3%, respectively. In rats, cure from the primary infection of C. sinensis increased resistant to reinfection, and the greatert the worm burden and the longer the duration of primary infection, the higher was the resistance rate. For primary infection doses of 10, 40 and 100 metacercariae per rat, the resistance rates were 87.4%, 93.8% and 98.4%, respectively. The resistance rates in rats after 2 or 8-week primary infection were 78.7% and 95.3%, respectively. All worms recovered from reinfected rats were immature. When cured rats were administered with methylprednisolone, resistance to reinfection became impaired. These findings indicate that rats develop a high degree of resistance to reinfection by C. sinensis after cure. The growths and maturations of reinfected worms were also impaired.
Animals ; Anthelmintics/administration & dosage/therapeutic use ; Anti-Inflammatory Agents/administration & dosage ; Clonorchiasis/*immunology/parasitology/*pathology ; Clonorchis sinensis/*pathogenicity ; Disease Models, Animal ; Female ; Hamsters ; Immunocompetence ; Immunosuppression ; Male ; Mesocricetus ; Methylprednisolone/administration & dosage ; Praziquantel/administration & dosage/therapeutic use ; Rats ; Rats, Sprague-Dawley ; Support, Non-U.S. Gov't

OBJECTIVETo establish the methods for isolation, purification and function identification of Syrian golden hamster islets.

METHODSThe Langerhans islets were isolated and purified from golden hamster pancreas by intra-ductal collagenase V perfusion and discontinuous Ficoll density gradient centrifugation. After isolation, the islet yield and purity were evaluated with DTZ staining. The islet function was assessed using glucose-stimulated insulin secretion test.

RESULTSThe total number of purified islets from one donor hamster was 359-/+35 islet equivalent (IEQ), with the purity and viability of the isolated islets of more than 90%. In response to glucose stimulations at 5.8 and 16.7 mmol/L, the secretion of insulin by the islets was 3.29-/+0.3 and 11.12-/+0.57 mU/L, respectively, showing a 2.28-fold higher insulin release by high-concentration than by low- concentration glucose stimulation (P<0.01).

CONCLUSIONThe methods of collagenase V digestion and gradient centrifugation result in high yield and high purity of the isolated hamster islets.

Animals ; Cell Separation ; methods ; Cricetinae ; Insulin ; secretion ; Islets of Langerhans ; cytology ; Male ; Mesocricetus

OBJECTIVETo investigate the effect of the secretory proteins of the ventral prostate on the glycoproteins in the oviductal fluid of golden hamsters.

METHODSMale golden hamsters were divided into four groups: sham operation (SH), total removal of accessory sex glands (TX), and retainment of the ventral prostate only (VP). Oviductal fluid was collected from female hamsters at 0.5, 2, 4 and 6 h after mating with the males of different operated groups with or without ventral prostate. Glycoproteins were probed with a panel of lectins and their changes in the oviductal fluid were analyzed by Western blot.

RESULTSThe 47 000, 52 000, 81 000 and 128 000 WGA-binding proteins were observed in the oviductal fluid of the 6 h TX group, the 32 000, 35 500, 47 000 and 52 000 WGA-binding glycoproteins noted in the 6 h VP group, the 47 000, 68 000, 95 000 and 128 000 pisum sativum agglutinin (PSA)-binding glycoproteins shown in the 6 h TX and VP groups, two extra 32 000 and 37 500 bands detected in the 6 h VP group, the 47 000 and 52 000 dolichos biflorus agglutinin (DBA)-binding glycoproteins present in the 6 h VP but absent in the 6 h TX group.

CONCLUSIONVentral prostate secretory proteins affect acetylglucosamine, N-acetylgalactosamine/galactose and mannose in the oviductal fluid collected 6 hours after mating. And these glycoproteins may play an important role in the development of embryos.

Animals ; Copulation ; physiology ; Cricetinae ; Fallopian Tubes ; metabolism ; Female ; Glycoproteins ; metabolism ; Male ; Mesocricetus ; Prostatic Secretory Proteins ; physiology

Animals ; Artemisinins ; pharmacology ; Cricetinae ; Leishmania donovani ; drug effects ; Male ; Mesocricetus ; Sesquiterpenes ; pharmacology

BACKGROUND/AIMS: It is well known that N-nitrosobis(2-oxopropyl)amine(BOP)-induced pancreas cancer and cholangiocarcinoma in Syrian hamster is similar to that of humans in morphological, biological and immunological aspects. The cyclic administration of BOP and ethionine, choline-deficient diet and methionine is known to rapidly induce the ductal type of carcinoma in pancreas and bile duct. Authors studied whether the rapid production of this cancer can occur in Syrian hamster and what its features are. METHODS: Sixteen Syrian hamsters aged 6-7 weeks and weighing 100 gm were used. All hamsters received 70 mg/kg body weight of BOP followed by three cycles of dl-ethionine, choline-deficient diet, l-methionine and 20mg/kg BOP. Hamsters were killed 9, 10 and 11 weeks after the beginning of the experiment and their gross and histologic features were observed. RESULTS: Nine cases, killed withan 10weeks after the begining of experiment, showed no development of cancer. Of seven Syrian hamsters, killed more than 10weeks after the begining of experiment, the incidences of BOP-induced cancer included one case(14.3%) of pancreas cancer and five cholangiocarcinomas( 71.4%). The morphological change of pancreas carcinogenesis was shown at first in cell mitosis and atypia(6 weeks) and then in atypical ductal hyperplasia(9 weeks) and carcinoma in situ(10 weeks). The change in cholangiocarcinoma, first progressed with ductular proliferation and surrounding fibrosis(6 weeks) followed by focal cholangiocarcinoma(10 weeks) and multiple invasive cholangiocarcinomas( 11 weeks). CONCLUSION: Pancreas cancer and intrahepatic cholangiocarcinomas can be induced rapidly within 10 weeks by cyclic injections of carcinogens in Syrian hamsters initiated with Nnitrosobis( 2-oxopropyl)amine and the morphologic changes can be observed.
Animals ; Bile Ducts ; Body Weight ; Carcinogenesis ; Carcinogens* ; Cholangiocarcinoma* ; Cricetinae* ; Diet ; Ethionine ; Humans ; Incidence ; Mesocricetus ; Methionine ; Mitosis ; Pancreas* ; Pancreatic Neoplasms*

PURPOSE: This study was carried out to investigate the effect of irradiation on the expression of proliferating cell nuclear antigen (PCNA) and apoptosis induction during the carcinogenesis in hamster buccal pouch. MATERIALS AND METHODS: Three months old Syrian golden hamsters were divided into control and 2 experimental groups. Hamsters in control group were left untreated on buccal pouchs. Twenty four hamsters were treated with 0.5% DMBA tri-weekly on the right buccal pouch. Forty eight hamsters were treated with 0.5% DMBA tri-weekly and irradiated with the dose of 5 Gy and 10 Gy at 6, 9, 12, 15 weeks after DMBA application. Resected buccal pouches were sectioned and examined for potential expression pattern of PCNA and apoptosis. RESULTS: The PCNA index was increased with the stages of buccal pouch epithelium carcinogenesis except the hyperplasia stage in control group (p<0.05). The irradiation did not effect on the PCNA index in the dysplasia and the carcinoma in situ stage, but in the hyperplasia stage, the PCNA index was increased with 10 Gy radiation and decreased in the carcinoma stage (p<0.05). The apoptotic index was significantly decreased from the carcinoma in situ stage and the lowest in the carcinoma stage. The apoptotic index was significantly decreased in the hyperplasia and dysplasia stage with the 5 Gy irradiation and significantly increased only in the carcinoma stage with the 10 Gy irradiation (p<0.05). CONCLUSION: The PCNA and apoptotic index were varied according to the irradiation period and dosage in each carcinogenesis stage.
9,10-Dimethyl-1,2-benzanthracene* ; Animals ; Apoptosis* ; Carcinogenesis* ; Carcinoma in Situ ; Cricetinae* ; Epithelium ; Hyperplasia ; Mesocricetus ; Proliferating Cell Nuclear Antigen* ; Radiation Dosage

OBJECTIVETo investigate the changes in serum interleukin-2 (IL-2) level in a hamster model bearing cheek pouch carcinoma after heavy ion beams irradiation.

METHODSThe serum levels of IL-2 were detected using enzyme-linked immunosorbant assay in 40 hamsters bearing cheek pouch carcinoma before and after exposure to heavy ion beam irradiation, with 8 normal animals as control.

RESULTSSerum IL-2 level was 0.16∓0.01 in the tumor-bearing hamsters before the irradiation, lower than that in the control group. After heavy ion beams irradiation at 4, 6, 8, and 12 Gy, serum IL-2 levels in the tumor-bearing hamsters were 0.18∓0.04, 0.22∓0.05, 0.15∓0.03, and 0.13∓0.04, respectively, showing a peak level after irradiation at 6 Gy and an obvious decrease following irradiation at greater doses.

CONCLUSIONHeavy ion beam irradiation causes alterations in serum IL-2 level with a dose-effect relation between them in hamsters bearing cheek pouch carcinoma.

Animals ; Cheek ; pathology ; Cricetinae ; Female ; Heavy Ions ; therapeutic use ; Interleukin-2 ; blood ; Male ; Mesocricetus ; Mouth Neoplasms ; blood ; radiotherapy

To establish the in vitro culture system of primordial germ cells (PGCs) of golden hamsters, PGCs of hamster were isolated from genital ridge of embryos at 10. 5th dpc (day post coitum), obtained by enzyme-mechanical method, and cultured on feeder cells. Then the PGCs were identified by alkaline phosphatase (ALP) activity staining. In order to induce the PGCs to differentiate in vitro, we removed the differential inhibition factors in the conditioned medium and observed the formation of embryoids and differentiated cells from three layers. The result showed that the pluripotent primordial germ cells could be successfully obtained from the golden hamsters at 10. 5th dpc by the enzyme-mechanical method and that PGCs were identified by both their strong positive reaction in ALP activity staining test and their differentiation into three-layer derived cells in vitro. The result suggests that the establishment of in vitro PGCs culture system of golden hamsters will provide new cell source for biomedical engineering.
Animals ; Cell Culture Techniques ; methods ; Cell Differentiation ; Cells, Cultured ; Cricetinae ; Embryo, Mammalian ; cytology ; Germ Cells ; cytology ; Mesocricetus

OBJECTIVETo clone down-regulated genes in neural tube defects of golden hamster induced by hyperthermia and to explore the molecular mechanism.

METHODSA reversed subtractive cDNA library was constructed using suppression subtractive hybridization. Clones with inserts were selected by combination of alpha complementary phenomenon and colony PCR. Then sequence and homology analysis of the inserts were made. And mRNA expression conditions were confirmed by Northern blot.

RESULTSThe reversed subtractive cDNA library was successfully constructed. Fifteen recombinant clones were sequenced and recognized homologous to known genes. The results of Northern blot showed that all these genes were down-regulated in defected neural tubes induced by hyperthermia compared to normal developed neural tubes.

CONCLUSIONSome important genes are identified which might be involved in neural tube defects induced by hyperthermia.

Animals ; Blotting, Northern ; Cloning, Molecular ; Cricetinae ; Female ; Gene Library ; Hyperthermia, Induced ; adverse effects ; Mesocricetus ; Neural Tube Defects ; etiology ; genetics