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Background/Aims: Plant growth regulators are considered to leave minimal amounts of remnants and therefore cause no significant side effects in humans. In this study, we aimed to investigate the hormonal and histopathological effects of 4-chlorophenoxy acetic acid (4-CPA), a commonly used plant growth regulator, on the gonadal functions of rats. Methods: The study was implemented on 64 Wistar albino rats (20 days old). Forty-eight rats received 4-CPA every day until 50 days of age. The rats were randomized into 4 groups (a control group and three 4-CPA groups with doses of 25, 50 and 100 mg/kg/day); each group was further divided into males and females, making a total of 8 groups. The levels of FSH, LH, testosterone, estradiol, leptin, inhibin-B and neuropeptide-Y were measured. Histopathological examination of the testes and ductus deferens in male rats, and ovaries and uterus of female rats (caspase-3 and -9 immunoreactivity) was performed. Results:Although hormone levels were similar between the groups, rats that received 4-CPA showed significantly higher degrees of apoptosis compared to the control group (p < 0.001) and increased doses of 4-CPA were directly correlated with the amount of apoptosis (p < 0.001). Conclusion: 4-CPA induced apoptosis in the gonads of rats without concurrent changes in plasma hormone levels.

Summary Purpose: We aimed to define the morphologic effects of valproate (VPA) and oxcarbazepine (OXC) on ovarian folliculogenesis in rats. Methods: Forty female wistar rats (21–24 days old and weighted between 46.4 and 55.3 g) were divided equally into 4 experimental groups, which were applied tap water (control group), 300 mg/kg/day VPA, 100 mg/kg/day OXC, and both VPA and OXC via gavage for 90 days. Ovaries of the rats on proestrous and diesterous phase of estrous cycle according to daily vaginal smear were taken out and placed in a fixation solution. Immunohistochemical and apoptosis (TUNEL) staining protocols were applied. Results: The number of follicles decreased and that of corpora lutea increased significantly in OXC, VPA, and OXC+VPA treated groups compared with control group (p < 0.05). The number of TUNEL positive ovarian follicles was 1.40 ± 0.52 in control group, but it significantly increased to 3.50 ± 0.53, 3.50 ± 0.53, and 4.90 ± 0.88 in VPA, OXC, and VPA+OXC groups (p < 0.0001). The increase in the number of TUNEL positive granulosa cells was also significant for OXC and VPA+OXC groups (p < 0.0001). Immunohistochemical HSCORE decreased for TGFβ1 and IGF1 staining and increased for P53 staining in all drug groups compared with control group (p < 0.001). Intensity of P53 labeling increased, while intensity of TGFβ1, IGF-1, and GDF-9 immunoreactivity decreased significantly in all drug groups compared with control group (p < 0.001). Conclusion: Long-term treatment with VPA or OXC from prepuberty to adulthood causes apoptosis and deterioration of folliculogenesis in rat ovarian follicles.

Objectives: The aim of this study is to determine the effectiveness of topical doxycycline used in the process of experimental myringosclerosis and tympanosclerosis. Study Design: A prospective experimental animal study. Methods: Experimental tympanosclerosis was accomplished in 25 healthy adult guinea pigs by inoculation with 2.5 × 107 colony-forming units of type-3 Streptococcus pneumoniae microorganisms followed by bilateral myringotomy. While the animals' right ears received a topical doxycycline treatment daily, their left ears were left untreated and used as controls. Otomicroscopic examination was carried out weekly and healing tympanic membranes were remyringotomized. After a 6-week follow-up, the temporal bones of 24 of 25 animals were removed and light-microscopy examination was done regarding tympanic membrane myringosclerosis and middle ear mucosal sclerosis. Results: Myringosclerosis was noticed to a lesser extent in the doxycycline-treated group when compared to the untreated control group. Light microscopy evaluation revealed a difference in the area and thickness of the sclerotic plaques of myringosclerosis of the tympanic membranes in the doxycycline-treated group and the control group, being significantly smaller and thinner in the treated group (P < .001, P < .04, respectively). Similarly, the area and thickness of the sclerotic plaques in the middle ear mucosa were significantly smaller and thinner in the doxycycline treated group (P < .001, P < .03). Conclusion: This study demonstrated that the potent matrix metallo-proteinase inhibitor doxycycline plays a preventive role in the development of experimentally induced tympanosclerosis.

The aim of the present study was to examine the effects of subchronic methyl parathion (MP) administration on lipid peroxidation and fallopian tube damage, and to evaluate the preventive effects of the use of vitamins E and C against toxicity. The experimental groups were: rats treated with corn oil (control group), with 5 mg/kg MP and with 5 mg/kg body weight MP plus vitamins E and C (MP + Vit). The groups were given MP by oral gavage for five days a week for four weeks at a daily dose of 5 mg/kg (MP and MP + Vit) using corn oil as a vehicle. Vitamins E and C were injected at doses of 50 mg/kg intramuscularly and 20 mg/kg intraperitoneally, respectively, just after the treatment with MP in the MP + Vit group. The levels of malondialdehyde (MDA) were determined in rat plasma. Electron microscopic ultrastuructural and histopathological changes in the fallopian tissue were examined. MDA levels were higher in the MP group than in the control group, and lower in the MP + Vit group than in the MP group. MP led to deletions in microvilli and marked loss in kinocillia of surface epithelium. But these marked histopathological findings decreased in the MP + Vit group. Multiple doses of MP administration caused some damage in the fallopian tube, and treatment with vitamins E and C after MP could reduce this effect. Toxicology and Industrial Health 2007; 23: 429—438.

Fluoride is a strong, hard anion and cumulative toxic agent. The effect of fluoride intoxication on lipid peroxidation in endometrial tissue and the protective effects of combinations of vitamins E and C in rats were studied. Additionally, the apoptotic changes in er dometrial tissue were examined. Experimental groups were as follows: control group; a group treated with 100 mg/l fluoride (F group); and a group treated with 100 mg/l fluoride plus vitamins E and C (F + Vit group). The F and F + Vit groups were treated orally with fluoride for 30 days. Vitamins E and C were injected simultaneously at doses of 50 mg/kg day i.m. and 20 mg/kg day body weight i.p. Extensive formation of DNA strand breaks, the typical biochemical feature of apoptosis, was detected with the use of the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick and labeling (TUNEL) method. Malondialdehyde (MDA) levels were determined in uterine tissue of rats. Fluoride caused a significant increase in NIDA levels (an important marker of lipid peroxidation) in the fluoride group compared with the controls (p < 0.05). Vitamins E and C significantly reduced the fluoride-induced lipid peroxidation in the F + Vit group compared with the F group (p < 0.05). Diffuse apoptosis in glandular epithelium and stromal cells was found in endometrial tissues of F treated rats by TUNEL method. The severity of these lesions was reduced by the administration of vitamins. From these results, it can be concluded that subchronic fluoride administration causes endometrial apoptosis, and lipid peroxidation may be a molecular mechanism involved in fluoride-induced toxicity. Furthermore, treatment with a combination of vitamins E and C reduced endometrial apoptosis caused by fluoride. (c) 2006 Elsevier Ireland Ltd. All rights reserved.

Objective. The aim of the present study is to figure out the immunohistochemical expression of transforming growth factor-α (TGF-α), epidermal growth factor (EGF), and vascular endothelial growth factor (VEGF) in hyperstimulated rat ovaries. Methods. Twenty Wistar-Albino adult female rats (250-300 g) were taken into the study. The animals were randomly divided into two groups, each containing 10 rats: (i) stimulation group and (ii) control group. In the stimulation group, a stimulation regimen was administered to induce follicular maturity and ovarian hyperstimulation syndrome (OHSS) at the end using a 30-IU follicle-stimulating hormone that was administered subcutaneously for 4 consecutive days, followed by a 30-IU human chorionic gonadotropin on day 5 to induce ovulation. The rats, in the control group, received 0.2 ml of 0.9% NaCl for 5 consecutive days to mimic the conditions of the study animals. At the end of the treatment period, all rats underwent ovariectomy and the sections of ovaries were stain...

Background Periosteal adventitia is believed to consist of fibrous tissue without any regenerative potential. This theory results in the assumption that surgically stripped periosteum which is also adventitial has no bone regeneration potential. We decided to test whether the periosteal adventitia is osteoinductive and whether it is suitable for a commonly faced clinical situation in an animal model. Methods This study used 24 femurs from 12 rabbits, which were separated into 3 groups. Lateral femoral condylar cavitary defects were created with a 5 mm drill bit. In group I, the defects were left empty as the control. In group II, the defects were only filled with ceramic graft particles. In group III, the defects were filled with a mixture of ceramic graft particles and autogenous, adventitial, periosteal particles. All animals were sacrificed at the end of the 6th week and were evaluated histologically. Results The microscopy of 3 different histologists suggested that group III had far superior healing when compared to the control group and group II. The statistical evaluation of the histomorphometrically gathered quantitative results revealed a meaningful increase in woven bone and a decrease in fibrous tissue in group III, confirming the histological analysis. Conclusions In this study we observed that the composite graft obtained by mixing ceramics and free adventitial periosteal grafts offers healing potential surpassing both the ceramic-only group as well as the control group. We conclude that adventitial periosteal graft greatly facilitates new bone formation.

The mechanism of tamoxifen-associated endometrial hyperplasia and cancer is not elicited. RAD001 inhibits a target protein in phosphatidyl kinase pathway, which is involved in endometrial hyperplasia and cancer. We investigated whether endometrial hyperplasia can be prevented through inhibition of the target of rapamycin by RAD001. Sixty BALB/c mice underwent oophorectomy and were divided into 6 groups: group 1, placebo group; group 2, tamoxifen-treated (4 mg/kg per 24 hours); group 3, estradiol-treated (4 mg/kg per 24 hours); group 4, RAD001-treated (1.5 mg/kg per 24 hours); group 5, tamoxifen (4 mg/kg per 24 hours)-and-RAD001 (1.5 mg/kg per 24 hours)-treated; and group 6, estradiol (4 mg/kg per 24 hours)-and-RAD001 (1.5 mg/kg per 24 hours)-treated. The count of glands, the length of epithelium, and immunohistochemical staining of proliferating cell nuclear antigen were analyzed. The count of total glands and the epithelial length were 30.8 (7.1) and 126 (43.4) μm, 53 (8.1) and 162.5 (34.8) μm, 65.2 (13.6) and 401.4 (44.0) μm, and 82.0 (5.2) and 444.7 (57.8) μm in the placebo-, the RAD001-, the tamoxifen-, and the estradiol-treated groups, respectively (P < 0.05). Although addition of RAD001 to estradiol did not decrease the count of total glands and the epithelial length, addition of RAD001 to tamoxifen did (43.3 [13.3] and 218.0 [29.2] μm, P < 0.05). The immunoreactive score of proliferating cell nuclear antigen is significantly decreased by the addition of RAD001 to either tamoxifen or estradiol in the epithelial and glandular cells. RAD001 can prevent tamoxifen-associated and estrogen-related endometrial hyperplasias in mice. RAD001 also decreases stromal cell proliferation in the tamoxifen-treated mice.

Conclusion. The results suggest that vitamin A can prevent scar formation in the vocal fold after surgery. Objectives. This study aimed to evaluate the effects of topically applied vitamin A on healing after vocal fold trauma. Materials and methods. Vocal folds of 20 adult rabbits were traumatized unilaterally. Ten of them were treated with topical application of vitamin A and the others served as controls. All animals were sacrificed after 10 days. Vocal folds were resected for analysis by light microscopy. Results. The untreated vocal folds showed extensive deposition of collagen and fibroblast on light microscopy and vocal folds treated with vitamin A showed less deposition. There was a significant difference between the two groups according to the percentage of collagen and fibroblasts in the lamina propria (p0.01).

Objectives: This study aimed to evaluate the ability of topically applied calcium channel blockers (diltiazem) to reduce the progression of experimentally induced myringosclerosis and tympanosclerosis. Study Design: Animal model. Experimental prospective study. Methods: The study included 25 adult albino guinea pigs that were bilaterally myringotomized and inoculated with a suspension of Streptococcus pneumonia type 3. The right ears were treated with topical application of diltiazem, and the untreated left ears served as the control group. Otomicroscopy and remyringotomy were conducted every week. One animal was sacrificed after 1 week and the remaining at the end of 6 weeks. Temporal bones were dissected, and tympanic bullae were analyzed with light microscopy. Results: The untreated control ears showed evidence of extensive myringosclerosis on otomicroscopy, and the ears treated with calcium channel blockers did as well although to a lesser degree. Under light microscopy, the lamina propria of both tympanic membranes and middle ear mucosae of the control group exhibited thicker (P < .1 and P < .05, respectively) and larger (P < .01 and P < .01, respectively) sclerotic tissue in comparison with the treatment group. Conclusion: The results suggest that calcium channel blockers had an influence in the prevention of tympanosclerosis.

The effects of metformin on S6K1, which is a crucial effector of mTOR signaling, and on endometrium were studied in a mouse model of endometrial hyperplasia induced by unopposed estradiol or tamoxifen.Forty-eight oophorectomized Balb/c mice were randomly assigned to receive saline, tamoxifen citrate (4 mg/kg), 17-beta estradiol hemihydrate (4 mg/kg), metformin (50 mg/kg), tamoxifen citrate (4 mg/kg) with metformin (50 mg/kg), or estradiol (4 mg/kg) with metformin (50 mg/kg) for 3 days. Histological markers of uterotrophy, including luminal epithelial cell height and density of endometrial glands were quantified for each slide. Immunohistochemical expression of PCNA and S6K1 was evaluated. H-score was used for S6K1 expression. Statistical analysis was performed using Student's t-test for comparison of two continous variables and one-way ANOVA for comparison of multiple variables.Mice treated either with tamoxifen or estradiol had significantly increased density of endometrial glands and epithelial heights compared to vehicle-only or metformin-only group (p0.001). Addition of metformin to tamoxifen or estradiol treated mice significantly decreased the density of endometrial glands and epithelial cell heights (p0.05). Addition of metformin to tamoxifen significantly decreased the H-score of S6K1 (p0.05) and the immunohistochemical expression of PCNA (p0.05) in uterine lining epithelium, glandular and stromal cells. Addition of metformin to estradiol significantly decreased the H-score of S6K1 (p0.05) and the immunohistochemical expression of PCNA (p0.05) in uterine lining epithelium, glandular and stromal cells.Metformin seems to have possible antiproliferative effects on the endometrium of estradiol or tamoxifen treated mice via inhibiting the mTOR mediated S6K1 activation.

Methylphenidate, more commonly known as Ritalin, is a piperidine derivative and is the drug most often used to treat attention deficit/hyperactivity disorder, one of the most common behavioural disorders of children and young adults. Our aims were to investigate dose-dependent immunohistochemical D2 expression and ultrastructural changes of the rat heart tissue, and to demonstrate possible toxicity of the long-term and high dose use of the methylphenidate. In this study, 27 female pre-pubertal Wistar albino rats, divided into three different dose groups (5, 10 and 20 mg/kg) and their control groups, were used. They were treated orally with methylphenidate dissolved in saline solution for 5 days/week during 3 months. At the end of the third month, after perfusion fixation, left ventricle of cardiac tissue was removed. Paraffin, semi-thin and thin sections were collected and immunohistochemical, terminal deoxynucleotidyl transferase-mediated Dig-dUTP nick end labelling assay and ultrastructural studies were performed. In conclusion, we believe that Ritalin is dose-related affecting dopaminergic system to increase heart rhythm and contraction. Thus, this drug may cause degenerative ultrastructural changes in mitochondrial path.

We aimed to investigate the effect of subchronic administration of dichlorvos (DDVP) on endometrium and to evaluate ameliorating effects of a combination of Vitamins E and C against DDVP toxicity in the rat. Three groups of rats were used in the experiment. The first group was treated with 4 mg/kg DDVP; the second group was treated with 4 mg/kg body weight DDVP plus Vitamins E and C (DDVP + Vit); the third group was given only corn oil (control). DDVP and DDVP + Vit groups were given DDVP by gavage 5 days a week for 4 weeks at a dose level of 4 mg/kg day by using corn oil as the vechicle. Vitamins E and C were injected at doses of 50 mg/kg i.m. and 20 mg/kg body weight i.p. Histopathological and immunohistochemical examinations for caspase-3 and caspase-9 were accomplished in the endometrium. The level of malondialdehyde (MDA) increased significantly in the DDVP group compared with the control group (p < 0.05). MDA significantly decreased in the DDVP + Vit group compared with the DDVP group (p < 0.05). Administration of Vitamins E and C along with DDVP significantly reduced the histopathological changes and the extent of apoptosis. In conclusion, subchronic DDVP administration caused endometrial damage and that treatment with a combination of Vitamins E and C reduced endometrial damage caused by DDVP. (c) 2006 Elsevier Inc. All rights reserved.

The aim of the present study is to figure out the immunohistochemical expression of transforming growth factor-alpha (TGF-alpha), epidermal growth factor (EGF), and vascular endothelial growth factor (VEGF) in hyperstimulated rat ovaries.Twenty Wistar-Albino adult female rats (250-300 g) were taken into the study. The animals were randomly divided into two groups, each containing 10 rats: (i) stimulation group and (ii) control group. In the stimulation group, a stimulation regimen was administered to induce follicular maturity and ovarian hyperstimulation syndrome (OHSS) at the end using a 30-IU follicle-stimulating hormone that was administered subcutaneously for 4 consecutive days, followed by a 30-IU human chorionic gonadotropin on day 5 to induce ovulation. The rats, in the control group, received 0.2 ml of 0.9% NaCl for 5 consecutive days to mimic the conditions of the study animals. At the end of the treatment period, all rats underwent ovariectomy and the sections of ovaries were stained for the TGF-alpha, EGF, and VEGF.The expression of TGF-alpha, EGF, and VEGF in the endothelium, the stroma, the granulosa cells, and the corpus luteum was found to be significantly higher in the stimulated group, compared to that in the control group ( p0.05).TGF-alpha, EGF, and VEGF are found to have increased in the hyperstimulated ovaries and this finding seems to be involved in the OHSS pathogenesis.

Objective To determine the effect of angiotensin-converting enzyme-inhibiting therapy on the expression of vascular endothelial growth factor (VEGF) in the hyperstimulated rat ovary. Design Experimental study. Setting University animal research laboratory. Animal(s) Thirty Wistar albino adult female rats were studied; 20 rats were stimulated with gonadotropins (groups 1 and 2), and 10 were controls (group 3). Ten of the stimulated rats received additional treatment with enalapril (group 2). Intervention(s) At the end of the treatment period, rat ovaries were subjected to immunohistochemical staining with anti-VEGF antibodies. Main outcome measure(s) VEGF staining intensity was graded semiquantitatively, and the H-score was calculated by light microscopic examination of the groups. Result(s) VEGF expression was found to be significantly higher in the endothelium and stroma in groups 1 and 2 compared with group 3. Although VEGF immunoreactivity was lower in the stimulation regimen plus enalapril group compared with the stimulation regimen–only group, the difference was insignificant. Conclusion(s) Enalapril does not seem to have a significant effect on VEGF expression in the hyperstimulated rat ovary. Because angiotensin II exerts its multiple actions via specific receptors, there may be other factors, such as a receptor blockade, that contribute to the VEGF expression.