Browsing by Subject "rat"
Now showing 1 - 4 of 4
- Results Per Page
- Sort Options
Item Morphological and Proliferative Changes that Occur in Rat Retinal Progenitor Cells Following Incubation with Retinoic Acid and RPE-Secreted Proteins(2006-08-01) Heath, Allison K.; Rustin E. ReevesHeath Allison K., Morphological and Proliferative Changes that Occur in Rat Retinal Progenitor Cells Following Incubation With Retinonoic Acid and RPE-Secreted Proteins. Master’s of Science (Cell Biology and Genetics), August 2006, 67 pp., 12 figures, bibliography. The principal objective of this research is to characterize virally-transformed rat retinal progenitor cells following stimulation by retinal pigment epithelial (RPE) cell secreted proteins and retinoic acid. Progenitor cells were isolated from explants of postnatal rat RPE cell in vitro. Isolated progenitor cells were cloned, analyzed by microscopy and proliferation bioassays, to determine if cell proliferation occurred. The isolated progenitor cells were analyzed for differentiation by Western blot analyses and immunocytochemistry. The rat progenitor cells cultured in RPE secreted proteins proliferated, but did not differentiate as shown by the presence of nestin and vimentin in these cells. Retinoic acid caused other progenitor cells to proliferate and differentiate, which is seen through the bioassays and Western blot analyses.Item Oxazolone as a Model to Induce Edema in the Lower Limb of Rats(2018-05) Pastrana, Christopher; Hodge, Lisa M.; Simecka, Jerry W.; Mathis, Keisa W.; Sumien, NathaliePurpose. Peripheral edema is a condition characterized by the accumulation of excess interstitial fluid in distal tissues and commonly manifests in the arms or legs. Untreated complex peripheral edema can progress into chronic lymphedema as impaired fluid drainage and chronic inflammation cause irreversible damage to the surrounding tissue and local lymphatics. The overall goal of our research is to study the effectiveness of osteopathic manipulative medicine techniques (OMT) for the treatment of edema, infection and inflammation. The aim of this study was to evaluate oxazolone (OXA) as a model to induce acute inflammation and lower limb edema in the rat. Specifically, we hypothesized that a single application of OXA would induce a local inflammatory response and induce edema in the lower limb. Methods. Female Sprague Dawley rats, weighing 200-250 g, were used for this study. On day 0 the right lower limb was shaved and 750 µl of 5% OXA-acetone solution or 750 µl of a 5% phosphate buffered saline (PBS)-acetone solution vehicle (VEH) was applied to the exposed skin. Lower limb measurements were made at days 0 and 6 using a Vernier caliper. At day 6, the rats were euthanized, and the bilateral hind paws were removed above the calcaneus and weighed. The spleen and bilateral inguinal lymph nodes were removed, homogenized, centrifuged and cells were stained with phycoerythrin (PE) mouse anti-rat granulocytes, fluorescein (FITC) anti-rat CD3, and allophycocyanin (APC) anti-rat CD161 antibodies. The percentage of granulocytes, T cells and dendritic cells were measured by flow cytometry. Data were analyzed by analysis of variance (ANOVA) followed by Tukey-Kramer post-test or by Student's t-test. Comparisons were made between OXA and VEH groups at day 6 post-induction. Results. OXA did not induce significant (p[greater than]0.05) changes in either hind paw thickness or hind paw volume. OXA significantly (P[less than]0.05) increased the concentration of macrophages, neutrophils, and dendritic cells, and T cells within inguinal lymph nodes. Conclusions. OXA induced an acute local inflammatory response in the draining inguinal lymph nodes. However, as used in this approach, OXA did not induce peripheral edema. In future studies we will investigate alternate strategies to induce lower limb edema in the rat.Item Quantitative Proteomic Investigation of Estrogenic Endocrine-Disrupting Effects in the Rat Uterus(2016-05-01) Rahlouni, Fatima R.; Prokai, Laszlo; Lacko, Andras G.; Borejdo, JulianThe mammalian uterus is one of the most sensitive organs for estrogenicity. However, the widely used rat uterotrophic assay to assess known and potential estrogenic compounds only considers the uterine wet weight gain as an endpoint measurement. To complement this method with an advanced technology that reveals molecular targets, we analyzed changes in protein expression using label-free quantitative proteomic analysis by liquid chromatography–mass spectrometry from uterine protein extracts of ovariectomized rats after daily 17β-estradiol exposure for five days. We performed shotgun proteomic analysis of the uterus to identify candidate proteins for use as markers of estrogenicity. In addition, we mapped the differentially expressed proteins from untargeted analysis to signaling networks and biological processes through Ingenuity Pathway Analysis. We selected twelve of the top up- and down-regulated proteins for further evaluation by selected reaction monitoring-based targeted quantitation. Of the final six candidate markers, we verified all six as markers of estrogenicity by the application of the panel to testing rats exposed to a low and high dose of the known estrogenic compound bisphenol A. Altogether, the results of this study demonstrate the power of combining untargeted and targeted quantitative proteomic methods for a comprehensive analysis in rat uterus to evaluate changes in protein expression levels due to estrogen exposure, and to uncover candidate markers of estrogenicity in the development of a targeted proteomics panel.Item Rat Naphthalene Cataract Studies: Mechanisms and Prevention(1994-06-01) Xu, Guo-Tong; Thomas YorioXu, Guo-Tong, Rat Naphthalene Cataract Studies: Mechanisms and Prevention. Doctor of Philosophy (Biomedical Sciences/Pharmacology), June, 1994, 134 pp., 16 tables, 34 figures, references, 153 titles. The mechanism of naphthalene-induced cataract in rats and the preventive action of AL01576 (an aldose reductase inhibitor, ARI) were studied in both in vivo and in vitro systems. In the in vivo studies, cataracts were induced in five strains of rats (2 pigmented, 3 albino) by naphthalene feeding (1g/kg/day). The cataractous changes occurred in 1 week as watercleft and spoke-like opacities which merged to form a shell-like opacity in the deep cortex by 3 weeks. Semi-quantitation of the opacities with an arbitrary six-score grading system showed little difference in the cataract development between the pigmented and albino strains. Major biochemical changes observed were a decrease of 20%-30% in GSH by one week of feeding, the appearance of disulfide cross-linking of lens proteins by 3 weeks, and a more than ten fold increase in the content of protein-GSH mixed disulfide. Neither damage to lens membrane functions as measured by 3H-choline or 86Rb uptake or loss of Na+/K+-ATPase activity was detected AL01576 (10 mg/kg/day) completely prevented the naphthalene-induced lens changes in both pigmented and albino rats. These results indicate that pigmentation is not required for induction of naphthalene cataract in rats and suggest that tyrosinase action on naphthalene metabolites (such as 1- or 2- naphthol) is not involved in this cataract formation. The in vitro “naphthalene cataract” was established by exposing rat lens to each of 5 potential naphthalene metabolites in organ culture system (in modified TC-199 medium) for 48 hrs. When naphthalene dihydrodiol was used, both the morphological and biochemical changes in the lens were very similar to those observed in lenses of naphthalene-fed rats, and AL01576 completely blocked these in vitro changes as it did in vivo. Other naphthalene metabolites (1,2-dihydroxynaphthalne, 1-naphthol, 2-naphthol and 1,2-naphthoquinone) caused changes which were different from those induced by naphthalene in vivo and one of them was prevented by AL01576. Therefore, naphthalene in vivo and none of them was prevented by AL01576. Therefore, naphthalene dihydrodiol is the key naphthalene metabolite which reaches the lens via blood and aqueous humor and causes cataract when it is metabolized to 1,2-naphthoquinone. This mechanism is further supported by the detection of naphthalene dihydrodiol in the lens and aqueous humor of naphthalene-fed rats. Examples of various classes of ARI (AL01576, AL04114, Sorbinil and Tolrestat) were compared for their effects on the formation of naphthalene cataract and a dual cataract induced with simultaneous feeding of galactose and naph-thalene. Both AL01576 and AL04114 (spirohydantoin derivatives) completely prevented the changes in the lenses of naphthalene-fed rats. However, Sorbinil (another spirohydantoin ARI) demonstrated a much weaker efficacy in this model and the carboxylic acid ARI, Tolrestat, showed no efficacy at all. In the dual cataract, Tolrestat prevented galactose cataract formation and reduced the lens dulcitol accumulation but showed no protection against the shell-like opacity caused by naphthalene. On the other hand, AL01576 protected the lens from the cataractogenic action of both compounds. These results rule out the involvement of aldose reductase in naphthalene cataract formation. Furthermore, AL04114 (not a cytochrome P-450 inhibitor) showed a similar efficacy as AL01576 (a inhibitor of cytochrome) in naphthalene cataract prevention. Therefore, the inhibition of cytochrome P-450 may not be involved in the prevention of this cataract. Based on these findings and the fact that AL01576 prevents the changes induced by naphthalene dihydrodiol (ND) but not 1,2-naphthoquinone (NQ), a new mechanism for rat naphthalene cataract formation is proposed: naphthalene is converted by cytochrome P-450 to ND, which reaches the eye via the blood and penetrates into the lens. By the action of dihydroxynaphthalene which autoxidizes to form NQ and H2O2 production and thus causes cataract. AL01576 and AL04114 inhibit DDD activity, block NQ and H2O2 production and thus prevent the cataract formation.