Histological investigation of experimentally induced diabetes effects on the distribution of transforming growth factor (TGF beta), nuclear factor kappa b (Nf-KB), heat schock 90 beta (Hsp beta) and E-cadherin proteins in testicular tissue / Investigación histológica de los efectos de la diabetes inducida experimentalmente en la distribución del factor de crecimiento transformante (TGFß), nuclear factor kappa b (Nf-KB), y proteinas heat schock 90ß (Hsp90ß) y E-cadherina en tejido testicular

SUMMARY: Diabetes is a metabolic disorder characterized by high blood sugar levels and it causes complications in many systems, including the reproductive system. As a result of diabetic conditions, one of the mechanisms that can cause repression of reproductive activity is testicular oxidant stress. The identification of diabetes on the cell signaling molecules axis is still under discussion. The aim of this study was to determine the effect of Transforming Growth Factor (TGFβ), Nuclear Factor kappa B (NF-kB), Heat-schock 90β (HSP90β) signal pathways and E-cadherin cell adhesion molecule on infertility in diabetic rat testicular tissue. In our study, includes histological, molecular and biochemical analysis of testicular tissue removed at the end of the 2 weeks experiment period. A total of 14 adult male rats were divided as control and diabetes. No intervention was given to 7 male rats in the control group. For the diabetic group, 7 male rats were injected by intraperitoneal with a single dose of 55 mg/kg streptozotocin (STZ). TGFβ, NF-kB, HSP90β and E-cadherin proteins were immunohistochemically studied to investigate possible tissue damage, inflammatory process, cell stabilization and integrity due to diabetes. In order to determine oxidant stress, lipid peroxidation product malondialdehyde (MDA), glutathione (GSH) and glutathione peroxidase (GPx) analyzes were performed. Fibrosis, inflammatory changes and loss of spermatogenetic series are prominent findings in the diabetic group. On analysis of all the samples with immunostaining, in the diabetic group, TGFβ and NF-kB immunoexpression significantly increased, while Hsp90β and E-cadherin immunoexpression significantly decreased compared with control groups. Experimental diabetes was found to cause fibrosis, inflammation, disrupting cell adhesion and stabilization in testicular tissue. These results suggest that cellular therapy studies are needed for possible damage.

RESUMEN: La diabetes es una enfermedad metabólica caracterizada por niveles altos de azúcar en sangre y causa complicaciones en muchos sistemas, incluido el sistema reproductivo. Como resultado de las condiciones diabéticas, uno de los mecanismos que puede causar alteraciones en la actividad reproductiva es el estrés oxidativo testicular. La identificación de la diabetes en el eje de las moléculas de señalización celular aún está en discusión. El objetivo de este estudio fue determinar el efecto del factor de crecimiento transformante (TGFβ), el factor nuclear kappa B (NF-kB), las vías de señalización de Heat-Schock 90b (HSP90β) y la molécula de adhesión celular de E-cadherina sobre la infertilidad en testículo de rata diabética. Al término de dos semanas se realizaron análisis histológico, molecular y bioquímico del tejido testicular extraído. Las 7 ratas macho del grupo control no fueron intervenidas. Para el grupo de diabéticos, 7 ratas macho fueron inyectadas por vía intraperitoneal con una dosis única de 55 mg / kg de estreptozotocina (STZ). Se estudiaron inmunohistoquímicamente las proteínas TGFβ, NF-kB, HSP90β y E-cadherina para investigar el posible daño tisular, el proceso inflamatorio, la estabilización celular y la integridad debido a la diabetes. Para determinar el estrés oxidativo, se realizaron análisis del producto de peroxidación lipídica malondialdehído (MDA), glutatión (GSH) y glutatión peroxidasa (GPx). La fibrosis, los cambios inflamatorios y la pérdida de series espermatogenéticas son hallazgos destacados en el grupo de ratas diabéticas. En el análisis de todas las muestras con inmunotinción, en el grupo diabético, la inmunoexpresión de TGFβ y NF-kB aumentó significativamente, mientras que la inmunoexpresión de Hsp90β y e-cadherina disminuyó significativamente en comparación con los grupos control. Se encontró que la diabetes experimental causa fibrosis, inflamación, alteración de la adhesión celular y estabilización en el tejido testicular. Estos resultados sugieren que son necesarios estudios de terapia celular para verificar posibles daños.

In vitro investigation of the effect of matrix molecules on the behavior of colon cancer cells under the effect of geldanamycin derivative.

The chaperone-binding drug, 17-allylamino-17-demethoxygeldanamycin, has recently come into clinical use. It is a derivative of geldanamycin, an ansamycin benzoquinone antibiotic with anti-carcinogenic effect. Understanding the effect of this drug on the cancer cells and their niche is important for treatment. We applied 17-allylamino-17-demethoxygeldanamycin to colon cancer cell line (Colo 205) on matrix molecules to investigate the relationship of apoptosis with terminal deoxynucleotidyl transferase dUTP nick end labeling immunocytochemistry and related gene expression. We used laminin and collagen I for matrix molecules and vascular endothelial growth factor for angiogenic structure. We also examined apoptosis-related signaling pathway including mitochondrial proteins, cytochrome c, Bcl-2, caspase-9, Apaf-1 expression using real-time polymerase chain reaction. There was clear effect of 17-allylamino-17-demethoxygeldanamycin that killed more cells on tissue culture plastic compared to matrix molecules. The IC50 value was 0.58 µg/mL for tissue culture plastic compared with 0.64 µg/mL for laminin and 0.75 µg/mL for collagen I. The analyses showed that more cells on matrix molecules underwent apoptosis compared to that on tissue culture plastic. Apoptosis-related gene expression was similar in which Bcl-2 expression decreased and proapoptotic gene expression of the cells on matrix molecules increased compared to that on tissue culture plastic. However, the application of 17-allylamino-17-demethoxygeldanamycin was more effective for the cells on collagen I compared to the cells on laminin. There was also a decrease in angiogenesis as shown by the vascular endothelial growth factor staining. This was more pronounced by coating of the tissue culture plastic with matrix molecules. Our results supported the anti-cancer effect of 17-allylamino-17-demethoxygeldanamycin, and this effect depended on matrix molecules. This effect occurs through apoptosis, and related genes were also altered. All these genes may serve for novel target under the effect of matrix substrate. However, correct interpretation of the results requires further studies.

In Vitro Cytotoxicity of GuttaFlow Bioseal, GuttaFlow 2, AH-Plus and MTA Fillapex.

INTRODUCTION: The aim of the present in vitro study was to evaluate the cytotoxicity of different sealers including GuttaFlow Bioseal, GuttaFlow 2, AH-Plus and MTA Fillapex on L929 murine fibroblasts. METHODS AND MATERIALS: Samples of GuttaFlow Bioseal, GuttaFlow 2, AH-Plus and MTA Fillapex were fabricated in Teflon disks of 5 mm diameter and 3 mm thickness. L929 fibroblasts were exposed to the extracts of these materials for 3, 24, 72 and 168 h at 37°C with 5% CO2. Cell viability was evaluated by the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Apoptosis was evaluated by the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay. The data were analysed by ANOVA. RESULTS: GuttaFlow Bioseal was nontoxic at all experimental time points (P>0.05), whereas MTA Fillapex and AH-Plus were toxic (P<0.001). At 7 days, there were more viable cells in the GuttaFlow 2 group than in the control group, and MTA Fillapex was more cytotoxic than AH-Plus. There were more apoptotic cells in the MTA Fillapex and AH-Plus groups than in the other groups at 3 h (P<0.001). CONCLUSION: GuttaFlow sealers are less cytotoxic than MTA Fillapex and AH-Plus. At all experimental time points, there was no significant difference in the cell viability between the GuttaFlow Bioseal group and the control group.

Acute and Chronic Pretreatment With Atenolol Attenuates Intestinal Ischemia and Reperfusion Injury in Hypercholesterolemic Rats.

OBJECTIVE: To evaluate the protective effects of preinjury atenolol (acute v chronic) on apoptosis, contractility, oxidative stress, and inflammatory markers in hypercholesterolemic rats undergoing intestinal ischemia-reperfusion (I/R) injury. DESIGN: Prospective, experimental animal study. SETTING: University laboratory. PARTICIPANTS: Male Wistar rats (n = 32). INTERVENTIONS: Rats were divided into the following 4 groups: 1 group was fed a normal diet (ND) (group ND+NoAT [no atenolol]), and the other 3 groups were fed a high-cholesterol diet (HCD)-group HCD+NoAT, group HCD+ChAT (chronic atenolol, 3 mg/kg/day for 8 weeks), and group HCD+AcAT (acute atenolol, 1.5 mg/kg, given 5 minutes before intestinal clamping). All rats underwent I/R injury. The superior mesenteric artery was clamped for 60 minutes, then opened for 120 minutes (reperfusion). Apoptotic cells and stimulated contractions of ileal segments were examined. Tissue markers of intestinal I/R injury were examined. Intestinal malondialdehyde, superoxide dismutase, and nitrate/nitrite levels were measured. MEASUREMENTS AND MAIN RESULTS: The chronic atenolol group had fewer apoptotic cells and higher superoxide dismutase activity compared with the other groups. Intestinal contraction was higher in both atenolol pretreatment groups compared with the NoAT groups. Chronic and acute atenolol resulted in lower ileal levels of malondialdehyde and immunolabeling-positive cells (intestinal inducible nitric oxide synthase, endothelial nitric oxide synthase, interleukin-1, and interleukin-8) after I/R injury compared with the no atenolol groups. CONCLUSIONS: Both chronic and acute pre-I/R injury treatment with atenolol attenuated I/R injury in this hypercholesterolemic rat model. These findings should encourage future studies of atenolol in hypercholesterolemic patients undergoing procedures with a high risk of intestinal ischemia.

Neuroprotective effects of bone marrow-derived mesenchymal stem cellsand conditioned medium in mechanically injured neuroblastoma cells.

BACKGROUND/AIM: Bone marrow-derived mesenchymal stem cells (BMSCs) possess self-renewal characteristics that distinguish them from other cell types. Recent studies have focused on the effects of conditioned medium (CM) that includes the extracellular matrix. Here we examined the neuroprotective effects of BMSCs and CM on damaged neuroblastoma cells. MATERIALS AND METHODS: The cells were divided into five groups: 1) healthy controls, 2) damaged cells alone, 3) damaged cells treated with BMSCs, 4) damaged cells treated with CM, and 5) damaged cells treated with both BMSCs and CM. Neuroprotective effects were then evaluated based upon the levels of oxidative stress, antitransforming growth factor ß1 (anti-TGFß1) production, and apoptosis. RESULTS: Significant differences were observed between healthy controls and damaged cells (P < 0.001), as well as between damaged cells and those treated with BMSCs alone (P < 0.05), CM alone (P < 0.05), and both BMSCs and CM in combination (P < 0.01). Among the treated groups, the strongest neuroprotective effects were seen in cells treated with both BMSCs and CM. CONCLUSION: These results show that both BMSCs and CM exhibit neuroprotective effects in damaged neuroblastoma cells. The strongest benefits were seen following treatment with both BMSCs and CM.

The effect of testosterone treatment on urodynamic findings and histopathomorphology of pelvic floor muscles in female rats with experimentally induced stress urinary incontinence.

OBJECTIVE: In recent studies, it has been observed that androgen receptors are densely located in pelvic floor muscles. We aimed to investigate the effect of testosterone on urodynamic findings and histopathomorphology of pelvic floor muscles in rats with experimentally induced stress urinary incontinence. MATERIALS AND METHODS: Twenty-eight adult female rats were randomized into four groups. Group I: rats in which SUI was induced and single-dose testosterone was administered 30 days later, group II: rats in which SUI was induced and single-dose testosterone was administered within the same session, group III: rats in which SUI was induced and saline was injected intramuscularly 30 days later, and group IV: the sham group. In order to demonstrate objectively the curative and preventive role of testosterone in experimental model of SUI, urodynamic examination and histopathomorphological evaluation of levator ani muscle were performed. RESULTS: Myofiber areas in groups I and II were detected to be significantly larger than those of the control group (P < 0.001). Another parameter was leak point pressure value by urodynamy. Regarding this parameter, LPP values in groups 1, 2 and 4 were observed to be significantly higher than those of group 3 (P < 0.001). The results of the comparison among groups 1, 2 and 4 revealed no significance (P > 0.05), which indicates that testosterone provides continence in a similar way to the group in which sciatic nerve section was not performed. CONCLUSIONS: In the present study, it has been demonstrated that testosterone has both preventive and curative effects on rat models of experimental SUI.

Effect of growth hormone on small intestinal homeostasis relation to cellular mediators IGF-I and IGFBP-3.

AIM: To evaluate the effects of growth hormone (GH) on the histology of small intestines which might be related to the role of insulin like growth factor (IGF)-I, IGF-binding protein 3 (IGFBP-3) and its receptors. METHODS: Twelve week-old adult male Wistar albino rats were divided into two groups. The study group (n = 10), received recombinant human growth hormone (rGH) at a dose of 2 mg/kg per day subcutaneously for 14 d and the control group (n = 10) received physiologic serum. Paraffin sections of jejunum were stained with periodic acid shift (PAS) and hematoxylin and eosin (HE) for light microscopy. They were also examined for IGF-I, IGFBP-3 and IGF-receptor immunoreactivities. Staining intensity was graded semi-quantitatively using the HSCORE. RESULTS: Goblet cells and the cells in crypt epithelia were significantly increased in the study group compared to that of the control group. We have demonstrated an increase of IGF-I and IGFBP-3 immunoreactivities in surface epithelium of the small intestine by GH application. IGF-I receptor immunoreactivities of crypt, villous columnar cells, enteroendocrine cells and muscularis mucosae were also more strongly positive in the study group compared to those of in the control group. CONCLUSION: These findings confirm the important trophic and protective role of GH in the homeostasis of the small intestine. The trophic effect is mediated by an increase in IGF-I synthesis in the small intestine, but the protective effect is not related to IGF-I.

Bladder function recovery in rats with traumatic spinal cord injury after transplantation of neuronal-glial restricted precursors or bone marrow stromal cells.

PURPOSE: We investigated functional recovery of the lower urinary system in rats with spinal cord injury after transplanting neuronal restricted precursors/glial restricted precursors or neural cells derived from bone marrow stromal cells into the injured area of the spinal cord. MATERIALS AND METHODS: A total of 30 rats underwent experimentation in 4 groups, including group 1--sham operation, group 2--spinal cord injury plus neuronal restricted precursor/glial restricted precursor transplantation, group 3--spinal cord injury plus bone marrow stromal cell transplantation and group 4--spinal cord injury control. All rats in the 4 groups were investigated urodynamically and sacrificed on day 28 after transplantation. The cells transplanted into the injured spinal cord underwent histological investigation. RESULTS: Transplanted cells (neuronal and glial restricted precursors, and bone marrow stromal cells) were found to maintain a presence in the injured spinal cord area. Baseline pressure, maximum capacity, mean uninhibited contraction amplitude, mean voiding pressure, voided volume and post-void residual volume were significantly better in groups 2 and 3 than in group 4, while baseline pressure in group 2 was better than that in group 3. We found no significant difference among the groups according to mean uninhibited contraction frequency. CONCLUSIONS: Although neuronal/glial restricted precursor transplanted rats seemed to have more improvement, all rats in groups 2 and 3 showed some significant improvement in lower urinary system function. On the other hand, the level of this improvement was far from complete functional recovery.

A comparison of the neuroablative effects of conventional and pulsed radiofrequency techniques.

OBJECTIVES: To compare the neuroablative effects of pulsed radiofrequency (PRF) and conventional radiofrequency (CRF) techniques on the sciatic nerve, a peripheral nerve that includes motor, sensory, and autonomous fibers. METHODS: The study consisted of 5 groups of 6 adult male Wistar rats. In the control group, no procedure was performed. In the sham group, electrode placement was the same as the other groups, but radiofrequency energy was not given to the rats. In the CRF40 group, 40 degrees C CRF was applied to the rats for 90 seconds. In the CRF80 group, 80 degrees C CRF was applied for 90 seconds. In the PRF group, the rats received 45 V PRF, which did not exceed 42 degrees C for 240 seconds. Two days later, sciatic nerve samples were taken. All specimens were evaluated both with light and electron microscopy. Sciatic nerve morphology was analyzed to compare the effects of CRF and PRF. Kruskal-Wallis and Mann-Whitney U tests were used for comparing the means. RESULTS: Minimal damage was observed in the control group, but damage increased in the sham group and became increasingly more distinct in the PRF, CRF40, and CRF80 groups. DISCUSSION: Nerve tissues can be affected during any type of procedure, even during surgical applications. Our results suggest that PRF is less destructive than CRF for the peripheral nerves. However, this idea should also be investigated at the molecular level, and safety analysis should be performed for routine clinical practice.

Cell surface glycosylation diversity of embryonic thymic tissues.

In the thymus, glycosylation status of many cell surface molecules changes during the thymocyte maturation and selection processes. In this study, we evaluated the glycosylation changes and possible relationships with programmed cell death in the thymic tissues from mouse embryos at the days 14 (E14), 15 (E15), 16 (E16), 17 (E17) and 18 (E18) of embryonic development. In order to determine glycosylation changes we used three different plant lectins: peanut agglutinin (PNA), Maackia amurensis leucoagglutinin (MAL or MAAI) and Sambucus nigra agglutinin (SNA), which recognize core disaccharide galactose (1-3) N-acetylgalactosamine [Galbeta(1-->3)GalNAc], sialic acid linked (2-->3) to galactose [SAalpha(2-->3)Gal] and sialic acid linked to galactose [SAalpha(2-->6)Gal] structures, respectively. Our lectin histochemistry and lectin blotting studies indicated that glycosylation pattern was modified in thymocytes at the embryonic developmental stages analyzed. The immature cortical thymocytes were labeled by PNA, whereas medullary thymocytes were positive for MAL and SNA binding. Many medullary thymocytes exhibited alpha(2-->6)-linked sialic acid on their surface and this increased throughout the gestational stages. In the lectin blotting studies, different protein bands of various molecular weights were identified in thymocytes. Two of them were putatively identified as CD43 and CD45 glycoproteins. In addition, TUNEL (deoxynucleotdyltransferase-mediated dUDP nick end labeling) indicated that only PNA-positive cortical thymocytes were deleted in all embryonic stages. These results indicate that the glycosylation pattern was modified in thymocytes at all embryonic developmental stages, and these modifications can affect the T cell deletion, probably via the galectin-1 molecule in the embryonic thymus.

The effect of osteogenic medium on the adhesion of rat bone marrow stromal cell to the hydroxyapatite.

OBJECTIVE: To investigate the adhesive properties of bone marrow stromal cell (BMSC) on the hydroxyapatite (HA) particles and analyze their behavior. METHODS: The study took place in the Department of the Histology and Embryology, Celal Bayar University, Manisa and in the Department of Bioengineering, Ege University, Izmir, Turkey between 2004 and 2005. We cultured BMSC from the mature rat tibia and differentiated to the osteoblasts by osteogenic medium. The BMSCs were subcultured and were taken to the HA substrate. We measured their proliferation capacity and viability with MTT assay using the spectrophotometric method. Furthermore, we identified the osteoblast-like cells by immunohistochemical staining of osteonectin and osteocalcin and we analyzed the behavior of the cells on different sized HA particles by SEM at the end of 3 days incubation. RESULTS: Osteogenic medium caused the proliferation capacity of BMSC to speed up and the effects appeared earlier. We confirmed the osteoblastic differentiation by staining of most cells with osteoblastic markers. Subcultured cells were similarly adhesive to the HA particles and the osteogenic medium did not alter this behavior. They spread on the substrate similarly. Most of the cells demonstrated the cytoplasmic protrusion. Morphology of the cells did not change much with or without osteogenic medium. Different sizes of HA particles did not affect the adhesive properties of these cells except HA gel. The spreading and attachment ratios of the cells on HA gel were more than the others CONCLUSION: We found that there was heterogeneity in BMSC on differentiation capacity to the osteoblast, which was a sign of a subpopulation. Adhesive cells showed similar morphology and behavior under the effect of osteogenic medium. The only difference was the spreading capacity on the HA gel where cell used this substrate more effectively for adhesion.

The effects of botulinum-A toxin on bladder function and histology in spinal cord injured rats: is there any difference between early and late application?

PURPOSE: We explored the effects of early and late application of botulinum-A toxin (BTX-A) on reservoir function and histological bladder changes in spinal cord injured rats. MATERIALS AND METHODS: The study was done in 30 Sprague-Dawley rats randomly allocated into 5 groups. Group 1 of 6 rats underwent sham operation only. Group 2 of 6 rats underwent spinal cord transection. Group 3 of 6 rats underwent spinal cord transection followed by BTX-A application into the detrusor muscle 7 days later. Group 4 of 6 rats underwent spinal cord transection, followed by BTX-A application into the detrusor muscle 28 days later. Group 5 of 6 rats underwent spinal cord transection followed by saline injection into the detrusor muscle after 28 days. Spinal cord injury was created by transecting the cord at the T9 to T10 level. All rats underwent cystometric examination initially and on day 42 before sacrifice. The bladders were removed and examined histologically for fibrosis and hyperplasia. RESULTS: On cystometric examination BTX-A caused an improvement in baseline pressure, and the frequency and amplitude of uninhibited detrusor contractions (p <0.001). No significant differences were observed in maximal bladder capacity or urethral opening pressure (p >0.05). Histologically BTX-A led to decreased fibrosis and hyperplasia (p <0.001). No significant differences were found between histological or cystometric among the groups with respect to receiving BTX-A in the early and late periods (p >0.05). CONCLUSIONS: BTX-A has a functional and histological healing effect on detrusor hyperreflexia subsequent to spinal cord injury in rats. Although administering BTX-A in the early period had better quantifiable functional and histological outcomes compared to the late period, the difference was not statistically significant.

Cell division and cellular morphology of the chick retinal pigmented epithelial cells in culture: a time-lapse analysis.

OBJECTIVE: To investigate the patterns of cell division, movement and shape during early stages of development of the chick embryo retinal pigmented epithelial (RPE) cells and to evaluate the morphology of dissociated embryonic cells with regard to their proliferation capacity. METHODS: We conducted this study at the Department of Histology and Embryology, Celal Bayar University, Manisa, Turkey, between 2002 and 2003. We isolated the cells from chick embryos. We analyzed the images of the embryonic cells originated from neuroepithelia using a computer-based time-lapse acquisition system attached to a differential interference contrast microscope. RESULTS: Retinal pigmented epithelial cells, despite being dissociated, depict a colony-type growth. Cells in the periphery of the colony and those outside the colony showed a tendency to proliferate and migrate and retained contact with the neighboring cells during division. Characteristics of cytokinesis were separation from the neighboring cell while retaining an attachment point, became rounded, moved up and started to shake and ascend to disseminate to the substrate to complete the division. The round-up stage was non-significantly shorter when the cell was closer to the center of the colony. Cells that were in the periphery of, or outside the colony had a round-up time of over one hour while cytokinesis-to-adhesion time was around 5 minutes. However, when we found the cells in the center of the colony, the times were half-an-hour and 1.5 hours for the daughter cells, a 2-fold difference between daughter cells with regard to the duration of attachment. CONCLUSION: Cell division, migration and proliferation are complex procedures influenced by growth factors, cell adhesion, matrix molecules underneath and the signal mechanisms and can be studied in detail using time-lapse microscopy, immunohistochemistry and confocal microscopy.

Protective effect of leukotriene receptor antagonist montelukast on smoking-induced lung injury in Wistar rats.

Increased activation of alveolar macrophage, neutrophil and mast cell has been proven in cigarette smoking (CS)-related lung disorders (CSLD). An increased production of cysteinyl-leukotrienes (LTs), which are mediators secreted from the mentioned cells, in response to CS has been shown in humans. The protective effect of LT1 receptor-1 antagonist (LTR-1AT) on CSLD is, however, not known. In this study we aimed to determine whether there is any protective effect of a LTR-1AT, montelukast (MK), on CSLD in Wistar rats. Nine controls and twenty-three smoke-exposed rats were enrolled into this study. Controls were exposed to non-filtered air, and the smoke-exposed rats were exposed to CS for 6 h/day, 6 days/week for three weeks. The CS-exposed rats were also treated with 0.1 mg/kg/day of MK or saline. Morphometric criteria for lung injury were determined as the mean linear intercept of alveolar septa (Lm), the volume density of alveolar septa (Vvspt) and the density of the alveolar surface area per unit volume of lung parenchyma (Sva.pa). Lung mast cells (LMC), which are a major source of LTs, were also counted. Results showed that Lm of the control group was significantly lower and Vvspt, Sva.pa of the controls were significantly higher compared to those of the CS-exposed groups. Animals treated with MK had significant protection against CSLD. Lm was significantly higher and Vvspt, Sva.pa were lower in the saline group than in the MK-treated group. The number of LMC in the CS-exposed groups was also significantly higher than that in the control group. Based on these results, one can suggest that some part of the pathogenesis of CSLD may be related to an enhanced LTs synthesis and LTR-1AT. Therefore, montelukast may protect against active or passive smoking-induced lung injury and related disorders.

A histological analysis of the protective effect of ischemic preconditioning in the rat retina.

PURPOSE: Ischemic preconditioning (IP) protects the retina from the damaging effect of subsequent ischemia in vivo. We aimed to investigate the histological alterations induced by the protective effect of IP to the retina. METHODS: The eyes of the rats were rendered ischemic by intra-ocular pressure (IOP) elevation. IP procedure consisted of producing ischemia for 5 minutes. Sham operation was similar to IP procedure except the pressure elevation. The operational eyes of sham and IP group underwent 60 minutes of ischemia 24 hours after the first procedure. The eyes contralateral to the experimental eyes made up the control group. The eyes were histologically analysed one week after the ischemia. RESULTS: The total retinal thickness of the sham group was significantly less than total retinal thickness of the control group (p < 0.001). There was not a significant difference between control and IP group regarding the total retinal thickness (p > 0.05). The thickness of the inner retinal layers of the sham group were significantly less than corresponding retinal layers of the control group (p < 0.001). The inner plexiform layer (IPL) and inner nuclear layer (INL) thickness values of the sham group were significantly less than same layers of the IP group (p < 0.001). Ganglion cell layer (GCL) thickness of the IP group was significantly less than GCL thickness of the control group (p < 0.001). IPL thickness of the IP group was significantly less than that of control group's (p < 0.05). The GCL and total retinal thickness of the IP group were significantly more than thickness of the corresponding layers of the sham group (p < 0.05). CONCLUSION: IP considerably protects inner retinal layers from subsequent ischemic damage in a high IOP ischemic model. This endogenous process could further be utilized to tailor specific neuroprotective strategies for retinal cells.

The effect of tibolone on endometrial IGF-1 and IGFBP-1 levels in ovariectomized rats.

OBJECTIVE: The goal of this study was to search the effects of two different doses of tibolone on endometrial IGF-1 and IGFBP-1 levels in ovariectomized rats. METHODS: Eighteen adult, female, 80-90-days-old, Wistar rats with an average weight of 250 g underwent bilateral ovariectomy under general anesthesia. After waiting for 4 weeks, they were randomized into three groups to receive either oral tibolone in two different doses or placebo. The treatment was continued for 5 weeks, and then the rats were sacrificed and the endometria were analyzed. RESULTS: Low columnar epithelium of the endometrial surface, longer epithelium and stratified squamous epithelium were seen in the control, low-dose and high-dose groups, respectively. The staining intensity of IGF-1 was mild in control, and moderate in both treatment groups, the difference between control the treatment groups was significant (P=0.015 for group L, and P=0.03 for group H). The staining intensity of IGFBP-1 was moderate in control, and strong in groups L and H. Again the difference was significant between control and both treatment groups (P=0.039 for grup L, and P=0.03 for group H). No significant difference was noted between each treatment group for both IGF-1 and IGFBP-1. CONCLUSION: Tibolone caused histological changes in endometrium and stimulated IGF-1 and IGFBP-1 staining. Both low and high dose treatments led to moderate and strong staining intensities for IGF-1 and IGFBP-1, respectively. The strong staining intensity of IGFBP-1 is likely due to the progestagenic effect of tibolone.