The effect of exercise on plasma insulin, free fatty acid, and glucose uptake and glycogen concentration in soleus, and intravenous glucose tolerance of streptozotocin treated, diabetic Sprague-Dawley rats were studied. Diabetic-trained animals were subjected to a regular program of treadmill running for 4 weeks. Seventy-two hours after the last training session, basal and insulin-stimulated glucose uptake was studied in incubated strips (about 20 mg) of soleus muscle in vitro. Glucose tolerance was measured with intravenous infusion of 0.5 g glucose/kg body weight. In diabetic rats, training was associated with increase glucose uptake in basal and maximal insulin concentrations, decreased fasting glucose concentrations, and increased muscle glycogen levels, but there were no changes in glucose tolerance curve and plasma insulin concentrations. These results suggest that regular running program for 4 weeks improve responsiveness of insulin on soleus muscle, but fails to cause improvement of impaired intravenous glucose tolerance in mild degree streptozotocin induced diabetic rats.
Animals ; Body Weight ; Exercise* ; Fasting ; Glucose Tolerance Test* ; Glucose* ; Glycogen ; In Vitro Techniques ; Infusions, Intravenous ; Insulin ; Muscle, Skeletal ; Plasma ; Rats* ; Rats, Sprague-Dawley ; Running ; Streptozocin*

No abstract available.
Animals ; Mice* ; Spermatozoa*

No abstract available.
Adenosine Triphosphatases* ; Adenosine* ; Alkaline Phosphatase* ; Female ; Ovarian Follicle*

The influence of normal late pregnancy on insulin action and insulin secretion was studied in the Sprague-Dawley female rats. On 20th day after mating, intravenous glucose tolerance test(IVGTI) was performed in non pregnant control and pregnant rats. As results of IVGTT, glucose disappearance rate was not significantly different in both groups, but secretory response of insulin was significantly(p<0.05) increased in pregnant rat. And the ratio of insulin/ .glucose was significantly higher in pregnant rats, which means existence of insulin resistance. These insulin resistance was overcomed by increased secretory response of pancreatic insulin. Insulinogenic index( A insulin/glucose - 5 min) was highly significantly (r=0.62, p<0.01) correlated with progesterone concentration. Glycogen level and amounts of "C-glucose incorporated into glycogen after IVGTT were significantly(p<0. 05) decreased in the liver, but were not changed significantly in soleus. Glycogen synthase activity of soleus and liver was not differ significantly in the both groups. Insulin binding at varying concentrations of insulin to crude membrane of pregnant liver was not significantly different from control. In conclusions, although these pregnant rats were normal glucose tolerance due to increased secretory response of insulin, that was correlated with progesterone concentration, pregnant rat had insulin resistance. The mechanisms of insulin resistance were not related to defect of insulin binding phase and glycogen synthase, but suggest pre-receptor and/or postreceptor phase.
Animals ; Female ; Glucose ; Glucose Tolerance Test ; Glycogen ; Glycogen Synthase ; Humans ; Insulin Resistance* ; Insulin* ; Liver ; Membranes ; Pregnancy ; Progesterone ; Rats* ; Rats, Sprague-Dawley ; Receptor, Insulin

PURPOSE: Multiparametric flow cytometry is a powerful tool for analyzing the phenotypic, cell kinetic and ploidy heterogeneity of tumor cell populations. But there are major problems such as inaccurate results by the contribution of non-neoplastic cell contamination and the substantial spectral overlap of PI (propidium iodide) into PE (phycoery- thrin) fluorescent emissions on a standard flow cytometer. Recent studies suggested that the emission spectral overlap from PI into PE could be sufficiently compensated electrically and the cytokeratin, a marker for epithelial tumor cells, are successfully used in conjunction with DNA specific dye so as to obtain DNA profiles selectively for cytokeratin-positive tumor cells. The aim of this study was to investigate the feasibility that multiparametric analysis in heterogeneous cell populations of cell lines like solid tumors, which were stained triply with PE, fluorescein isothiocyanate FITC, and PI, can be done without any influences by the contaminated normal diploid cell populations and without spectral overlap between fluorochromes on a standard flow cytometer. MATERIALS AND METHODS: MCF-7 cell lines and heterogeneous cell populations mixed with MCF-7 cells and human peripheral blood lymphocytes were fixed with 1% paraformal- dehyde and permeabilized with 100% methanol. Cytokeratin was labeled with PE and some proliferat!on-associated markers were labeled with FITC, which were followed by DNA staining by PI. These triply stained cells were measured on a standard FACScan flow cytometer equipped with 488 nm single laser and those acquired data were analyzed with WinList 3.0 and ModFit LT software programs on personal computor. RESULTS: Coefficient of variation (CV) of GoG1> peak of MCF-7 cells alone was 4.3. GoG1, S, and G2M phase fractions were 44.9%, 45.9%, and 9.2% respectively. FITC, PE and PI fluorochromes could be detected without any interference between them. CVs of GoG1 peak of PBL and MCF-7 cells in those heterogeneous population were 2.3 and 4.2 respectively. The DNA index of MCF-7 cells was 1.7. MCF-7 cells expressed the cyto- keratin, PCNA, p53, c-erbB/2 and c-myc antigen and in contrast, PBL did not express cytokeratin. The cell cycle phase fractions and oncoprotein expressions could be detected separately in diploid PBL and aneuploid MCF-7 cells in the mixed cell population without any influences by each other. CONCLUSION: These results suggested that the cellular antigen expressions of the malignant cells can be analyzed selectively without influences of fluorescent signals from nonneo- plastic cells. The neoplastic tumor subpopulations are clearly identified on the basis of both ploidy status and antigen expressions. The positive cytokeratin expressions indicate that they were derived from the epithelium, providing objective evidence of the tissue of origin and more precise analysis of DNA contents, ploidy, and oncogene expressions selectively with possible correlation between them. Thus, this method offers new possibilities for multiparameter flow cytometric analysis in the heterogeneous solid tumor cell populations.
Aneuploidy ; Breast Neoplasms* ; Breast* ; Cell Cycle ; Cell Line* ; Diploidy ; DNA ; Epithelium ; Flow Cytometry* ; Fluorescein* ; Fluorescein-5-isothiocyanate ; Fluorescent Dyes ; Humans ; Keratins ; Lymphocytes ; MCF-7 Cells ; Methanol ; Oncogenes ; Phycoerythrin* ; Plastics ; Ploidies ; Population Characteristics ; Proliferating Cell Nuclear Antigen ; Propidium*