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Biomedical subjects

Hanefi Ozbek

Publications and source records attributed to Hanefi Ozbek.

At least 19 recordsLinked to original sources
PubMed2006

Analgesic and hepatotoxic effects of Ononis spinosa L.

The present study investigated the analgesic and hepatoprotective activities of a water extract of Ononis spinosa L. (OS) in mice. Analgesic activity was based on the pain thresholds measured with the tail-flick test before administration at 30, 90 and 150 min. The results were analysed with one-way variance analysis. The extract of Ononis spinosa showed analgesic activity equivalent to aspirin at 30 and 90 min and even higher than aspirin with the 50 mg/kg dose. At a dose of 100 mg/kg OS showed an analgesic effect equivalent to aspirin at all time points.The hepatoprotective influence of OS on carbon tetrachloride (CCl(4))-induced acute liver toxicity was also studied. The extract had no significant effect on the increased levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and bilirubin in CCl(4) treated animals (p > 0.05). Thus, the results reveal that the extract of OS had no hepatoprotective effect on CCl(4)-induced acute liver toxicity.

Alanine Transaminase↗
PubMed2006

The effect of colchicine on the peritoneal membrane.

Peritoneal dialysis (PD) is a treatment modality for patients with renal failure. Peritoneal fibrosis is one of the most serious complications after long-term continuous ambulatory peritoneal dialysis (CAPD). Histological studies in both humans and animals show that chronic peritoneal dialysis results in fibrosis of the peritoneal membrane. In our study, we investigated the effect of colchicine on peritoneal alterations induced by hypertonic PD solution in rats. Sprague-Dawley rats intraperitoneally received saline (control group) once daily, for 28 days, or 3.86% glucose (PDF group), or 3.86% glucose plus colchicine (colchicine group). Animals from each group were sacrificed after 28 days with anesthetized ketamine (60 mg/kg BW). For the PD fluid assessment, 1 h before the sacrifice of animals, 10 mL PD fluid of 2.27% glucose was given, and this fluid was obtained after the sacrifice. The levels of transforming endothelial growth factor beta (TGF-beta), tumor necrosis factor alpha (TNF-alpha) and albumin were investigated both in the peritoneal dialysate and blood, and the levels of malondialdehyde (MDA) were investigated only in peritoneal dialysate. The peritoneal membrane was evaluated histologically by light microscopy. When groups were compared in terms of body weight change, the colchicine group significantly lost weight compared to controls and PDF group (-4.7% + 4.5, 3.5% +/- 7.2, 3.0% +/- 1.3, respectively, p = 0.018). Also, the blood albumin level was significantly lower for these in the colchicine group compared to those in the PDF group (2.7 +/- 0.35 versus 3.2 +/- 0.3 g/dL, respectively, p = 0.048). The blood TGF-beta level was significantly lower in the control group, and no difference was observed between the PDF and colchicine groups (294.4 +/- 67.5 versus 787.4 +/- 237.4 versus 615.3 +/- 235.1 pg/mL, respectively, p = 0.004). The mesothelial thickness found in groups was as follows: control group 102 +/- 18.9 microm, PDF group 128.33 +/- 33.1 microm, colchicine group 117 +/- 35.6 microm (p = 0.34). In conclusion, a rat model for peritoneal dialysis associated peritoneal derangement without fibrosis could be induced. Colchicine could not prevent peritoneal derangement in this model.

Animals↗
PubMed2006

Acute amitriptyline intoxication: an analysis of 44 children.

The tricyclic antidepressant agents, particularly amitriptyline and dothiepin, are recognized for their potentially lethal cardiovascular and neurological effects in poisoned patients. In this article, the clinical and laboratory findings of 44 children with amitriptyline intoxication are reviewed. Our purpose was to investigate amitriptyline intoxication in childhood. Of 44 patients, 21 (47.7%) were boys, 23 (52.3%) were girls, and the ages ranged from 12 months to 14 years (mean +/- SD; 4.09 +/- 2.9 years). All children except one who took an overdose of amitriptyline to decrease his pain accidentally ingested an overdose of amitriptyline. The amount of amitriptyline ingested was between 2 mg/kg and 97.5 mg/kg (mean +/- SD; 13.6 +/- 17.7 mg/kg per dose) (the drug dosage was not known in 13 children). The most commonly observed clinical and laboratory findings were lethargy, tachycardia, convulsion, hyperglycemia and leukocytosis. In all patients except for two children who died the abnormal clinical and laboratory findings returned to normal within a few days after admission and they were discharged from the hospital in good health within the fourth day of admission. One of the children ingested 97.5 mg/kg amitriptyline and probably died due to status epilepticus and another child who died ingested 36 mg/ kg amitriptyline and died due to cardiopulmonary arrest. In conclusion, our findings showed that initial symptoms and signs of acute amitriptyline intoxication appeared severe, but they disappeared with only supportive care required in most children except for cases that ingested high doses of drug within a few days. In contrast to adults, we infrequently noted respiratory insufficiency, arrhythmia and hypotension in children with acute amitriptyline intoxication.

Adolescent↗
PubMed2006

Analysis of survival factors in patients with advanced-stage gastric adenocarcinoma.

BACKGROUND: Prognosis in patients with gastric cancer is determined by the tumor itself, as well as certain patient-related factors. MATERIAL/METHODS: In this study, 138 patients with high-grade gastric adenocarcinoma who were admitted to our hospital between September 1999 and April 2002 were retrospectively evaluated in terms of the effects of clinicopathological parameters and treatment approaches on survival by single and multiple variable analyses. Patients histopathologically diagnosed as having gastric adenocarcinomas with stage IV M0 (without distant organ metastasis) or stage IV M1, (with distant organ metastasis) were included in the study. RESULTS: Overall median survival time was 3.1 months and three-year survival rate was 8%. With single variable analysis, body mass index (BMI), clinical stage, surgery, type of surgery, and serum level of albumin were significant prognostic factors related to overall median survival time. Gender, clinical stage, surgery, type of surgery, hemoglobin concentration, and serum level of albumin were found to be significant prognostic factors related to survival without progression (p < 0.05). No surgical treatment, palliative surgery (compared with radical surgery), and BMI below 20 were found to be the statistically significant poor prognostic factors related to survival in multiple variable analysis. In terms of both overall survival and survival without progression, performing surgery or not was statistically the most significant independent prognostic factor. CONCLUSIONS: No surgical treatment, palliative surgery instead of radical surgery, and BMI below 20 on first admission were determined as poor prognostic factors related to survival in patients with high-grade gastric adenocarcinoma.

Adenocarcinoma↗
PubMed2005

Gastroprotective activity of Nigella sativa L oil and its constituent, thymoquinone against acute alcohol-induced gastric mucosal injury in rats.

AIM: To evaluate the role of reactive oxygen species in the pathogenesis of acute ethanol-induced gastric mucosal lesions and the effect of Nigella sativa L oil (NS) and its constituent thymoquinone (TQ) in an experimental model. METHODS: Male Wistar albino rats were assigned into 4 groups. Control group was given physiologic saline orally (10 mL/kg body weight) as the vehicle (gavage); ethanol group was administrated 1 mL (per rat) absolute alcohol by gavage; the third and fourth groups were given NS (10 mL/kg body weight) and TQ (10 mg/kg body weight p.o) respectively 1 h prior to alcohol intake. One hour after ethanol administration, stomach tissues were excised for macroscopic examination and biochemical analysis. RESULTS: NS and TQ could protect gastric mucosa against the injurious effect of absolute alcohol and promote ulcer healing as evidenced from the ulcer index (UI) values. NS prevented alcohol-induced increase in thiobarbituric acid-reactive substances (TBARS), an index of lipid peroxidation. NS also increased gastric glutathione content (GSH), enzymatic activities of gastric superoxide dismutase (SOD) and glutathione-S-transferase (GST). Likewise, TQ protected against the ulcerating effect of alcohol and mitigated most of the biochemical adverse effects induced by alcohol in gastric mucosa, but to a lesser extent than NS. Neither NS nor TQ affected catalase activity in gastric tissue. CONCLUSION: Both NS and TQ, particularly NS can partly protect gastric mucosa from acute alcohol-induced mucosal injury, and these gastroprotective effects might be induced, at least partly by their radical scavenging activity.

Animals↗
PubMed2005

A new agent for treatment of acute respiratory distress syndrome: thymoquinone. An experimental study in a rat model.

OBJECTIVE: Acute respiratory distress syndrome (ARDS) and acute lung injury (ALI) are important clinical problems in thoracic surgery and critical care medicine. Most of the treatment methods are still supportive. Thymoquinone has anti-inflammatory, spasmolytic, bronchodilator and antibacterial effects. We studied its effects on ALI/ARDS in a rat model. METHODS: ALI/ARDS was developed in 40 Sprague-Dawley male rats (200-250 g in weight) by intratracheal instillation of human gastric juice (pH 1.2). Rats were treated with mechanic ventilator for 3h. There were five groups: Control group (n=11); Steroid group (n=10); Ethanol group (n=5); Thymoquinone group (n=9) and Thymoquinone+Steroid group (n=5). No instillation except gastric juice was applied in the first group. Thymoquinone was given in dosage of 6 mg/kg, metilprednisolone in dosage of 10mg/kg, ethanol 0.75 ml/kg intraperitoneally (IP). Blood gas analysis and compliance measurement were done. At the end of the third hour, rats were sacrificed and their lungs were excised for histopathological examination. RESULTS: In the thymoquinone group, the ratio of arterial oxygen to the fraction of inspired oxygen (PO2/FiO2) was significantly better compared to the other groups (P=0.000-0.043). Static compliance measurements revealed higher values in thymoquinone and thymoquinone+steroid groups. Histopathological examinations showed that affected lung tissue is lower in groups 2 and 4 (P=0.000-0.027). CONCLUSIONS: This study revealed that thymoquinone improved oxygenation while both thymoquinone and steroids protect lung tissue from hazardous effects of human gastric juice (pH 1.2) histopathologically.

Acute Disease↗
PubMed2005

A comparison of effects of fluoroquinolones on fracture healing (an experimental study in rats).

BACKGROUND: The objective of the present study was to test and compare the effect of fluoroquinolones on fracture healing as assessed histopathologically. METHODS: A total of twenty five Wistar rats were arbitrarily assigned to five groups with five animals each. Bilateral closed femoral fracture was constructed manually in all groups. The first group did not receive any drug as control (C). The 2nd, 3rd, 4th, and the last group were treated with norfloxacin (N), ofloxacin (O), pefloxacin (P) and ciprofloxacin (Ci) respectively. Antibiotic administration was started on the 7th day after the fracture incident. All the treatments were discontinued twenty days after the incident all the rats were sacrificed , and the fracture calluses together with affected femurs were resected en bloc at the fourth week after fracture. RESULTS: Average healing grades of control group was higher than all the other antibiotic groups. Mean healing grades of control ( 5 ; n:8), ofloxacin (4.1; n:7), ciprofloxacin (3.9; n:8), norfloxacin (3.4 ; n:9) and pefloxacin groups (2.6 ; n:10) were recorded. Statistically significant differences between antibiotherapy groups ( excluding. norfloxacin) and the control group were detected. CONCLUSIONS: The current histopathological study has shown that all the studied fluoroquinolones retarded fracture healing in rats.

Animals↗
PubMed2004

The effect of Ginkgo extract EGb761 in cisplatin-induced peripheral neuropathy in mice.

Neuroprotective effect of Ginkgo biloba extract EGb761 in cisplatin (cis-diamminedi-chloroplatinum, or CDDP)-induced peripheral neuropathy was investigated. Swiss albino mice were treated with CDDP, 2 mg/kg ip twice a week for nine times. One group of the animals also received EGb761 in the drinking water at an estimated dosage of 100 mg/kg per day. Two other groups received vehicle (control) or EGb761 only. Development of neuropathy was evaluated with changes in sensory nerve conduction velocity (NCV). Following the treatments, dorsal root ganglia (DRGs) were microscopically examined and some were cultured for 3 days. EGb761 proved effective in preventing the reduction in NCV (P < 0.0001) caused by CDDP. CDDP caused a decrease in the number of migrating cells (P < 0.01) and in the length of outgrowing axons (P < 0.01) while EGb761 treatment prevented the latter. CDDP led to smaller nuclear and somatic sizes in neurons (P < 0.01), while with EGb761 co-administration, both were close to control values. Animals having EGb761 only had similar results with controls. In conclusion, EGb761 was found to be effective in preventing some functional and morphological deteriorations in CDDP-induced peripheral neuropathy.

Administration, Oral↗
PubMed2004

Cyclosporine reduces hepatic antioxidant capacity: protective roles of antioxidants.

The immunosuppressive agent cyclosporine A (CsA) has been reported to exert measurable hepatotoxic effects. One of the causes leading to hepatotoxicity is thought to be reactive oxygen radical formation. Therefore, this study was designed to elucidate possible relation between cyclosporine A treatment and antioxidant capacity (AOC) of hepatic tissue and, to determine if antioxidant supplementation is beneficial. Cyclosporine A was given to 20 rabbits orally for 10 days. Vitamins E and C combination were given intramuscularly. Vitamin therapy was started 3 days before cyclosporine A treatment and continued for 10 days. In each group (control, cyclosporine A, cyclosporine A+vitamin, and vitamin only) there were five animals. After the animals were sacrificed, their livers were removed to be used in the AOC measurement. AOC was found to be lower in cyclosporine A group compared to control and vitamin groups. Results suggest that reduced antioxidant capacity may play part in the cyclosporine A-induced hepatotoxicity and use of some antioxidants may give beneficial results.

Administration, Oral↗
PubMed2004

Hepatoprotective and anti-inflammatory activities of Ballota glandulosissima.

Water extract of Ballota glandulosissima Hub.-Mor & Patzak (Lamiaceae) (BG) was investigated for anti-inflammatory activity using the carrageenan-induced rat paw oedema test and for hepatoprotective effect on carbon tetrachloride (CCl(4))-induced hepatotoxicity in rats. Biochemical parameters of hepatic damage such as serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP) and bilirubin concentrations were determined. CCl(4) (0.8 mL/kg i.p. for 7 days) treatment increased the serum AST, ALT, ALP and bilirubin levels significantly as compared to controls. Treatment of animals with BG (100 mg/kg, i.p.) +CCl(4) (0.8 mL/kg i.p.) for 7 days significantly ameliorated the levels of AST, ALT and ALP elevated by the CCl(4) treatment alone. The results of biochemical tests were also confirmed by histopathological examination. BG together with CCl(4) treatment decreased the balloning degeneration but did not produced apoptosis of hepatocytes, centrilobular and bridging necrosis observed in the CCl(4) treatment alone. BG, at 100 mg/kg per os, showed a significant reduction (34.22%) in rat paw oedema induced by carrageenan. The reference anti-inflammatory drugs etodolac (50 mg/kg, p.o.) and indomethacin (3 mg/kg, i.p.) significantly reduced the oedeme by 43.42 and 95.70%, respectively. The present study reveals that the water extract of Ballota glandulosissima possesses promising protective activity against CCl(4) induced hepatic damage and anti-inflammatory activity in rats.

Animals↗
PubMed2004

Effects of garlic extract consumption on blood lipid and oxidant/antioxidant parameters in humans with high blood cholesterol.

Effects of garlic extract supplementation on blood lipid profile and oxidant/antioxidant status were investigated in volunteer subjects with high blood cholesterol. A total of 23 volunteer subjects with high blood cholesterol (>5.98 mmol/L) participated in the study. Of them, 13 patients were evaluated as a hypertensive group and the others a normotensive group. Before (first sample) and after (second sample) garlic extract consumption for 4 months, routine blood analyses including lipid parameters and liver and kidney function tests were performed. Additionally, blood oxidant (malondialdehyde [MDA], oxidation resistance [OR]), and antioxidant (antioxidant potential [AOP], nonenzymatic superoxide radical scavenger activity [NSSA]) parameters were measured. Serum total cholesterol, low-density lipoprotein (LDL) and very-low-density lipoprotein (VLDL) cholesterols, and triglyceride levels were found to be significantly lowered, but HDL high-density lipoprotein cholesterol level increased after the extract use. The total:HDL cholesterol ratio was also found to be significantly decreased after the extract use. There were no meaningful differences with regard to other routine biochemical parameters. Additionally, blood AOP, OR, and NSSA values were found increased and MDA level decreased in the second samples relative to the first ones. Systolic and diastolic blood pressure values were also found to be significantly lowered after extract supplementation in the hypertensive group, but no similar changes were observed in the normotensive group. We conclude that garlic extract supplementation improves blood lipid profile, strengthens blood antioxidant potential, and causes significant reductions in systolic and diastolic blood pressures. It also leads to a decrease in the level of oxidation product (MDA) in the blood samples, which demonstrates reduced oxidation reactions in the body.

Adult↗
PubMed2003

Effects of trimetazidine on submaximal exercise test in patients with acute myocardial infarction.

BACKGROUND: It was demonstrated that the novel metabolic agent, trimetazidine, could lessen the incidence and severity of angina, whether used in monotherapy or combination. Although the animal studies demonstrated that trimetazidine reduces myocardial infarct size anf improves recovery of mechanic function after ischemia, little is known on the potential benefits of trimetazidine in patients with myocardial infarction (AMI). The aim of this study was to evaluate the efficacy of trimetazidine on AMI by sub-maximal exercise test. METHODS: A double-blind crossover trimetazidine versus placebo trial was carried out in 44 patients with AMI. Patients with randomly allotted into trimetazidine (23 patients) or placebo (21 patients) for 5 days and underwent an initial sub-maximal exercise test. Exercise tests according to the modified Bruce protocol were performed. Exercise end points included completion of stage II or 75% of maximum predicted heart rate whichever came first. An average 12-lead ECG was obtained at rest, every minute during exercise, at the onset of anginal symptoms, at the onset of 1-mm ST segment depression, at peak exercise and every 2-minute during recovery. After the initial exercise tests, study groups resumed the drugs in the opposite order for 4 to 5 days and underwent a second sub-maximal exercise test. RESULTS: Exercise induced ST segment depression was noted in 17 patients (38.6%) receiving placebo. However, exercise induced ST-segment depression was observed in 8 patients (18.1%) taking TMZ. Positive exercise test results were significantly higher on placebo group than TMZ group (p=0.018). Additionally, trimetazidine prolonged the time to 1-mm ST-segment depression (6.1 +/-0.5 vs 4.9 +/-0.4, P< 0.031) and exercise duration (7.2+/-0.9 vs 5.8 +/-0.9, p<0.025). CONCLUSION: Trimetazidine therapy improves the exercise capacity and reduces evidence ischemia derived from sub-maximal post-infarction exercise testing.

Cross-Over Studies↗
PubMed2003

Anti-fibrogenic effects of captopril and candesartan cilexetil on the hepatic fibrosis development in rat. The effect of AT1-R blocker on the hepatic fibrosis.

BACKGROUND/AIM: Angiotensin converting enzyme (ACE) and angiotensin II (AT-II) have been suggested to play an important role in liver fibrogenesis. There is a significant relationship between inheritance of hightened expression of transforming growth factor beta1 (TGF-beta1) and AT-II and the development of progressive hepatic fibrosis. The purpose of this study was to investigate the effects of captopril, an ACE inhibitor and candesartan cilexetil, an AT-II type 1 receptor (AT1-R) blocker, on liver fibrosis induced in rats by carbon tetrachloride (CCl4) administration. METHODS: rats were divided into 4 experimental groups: The first group was given CCl4 alone; the second was given both CCl4 and captopril (100 mg x kg(-1) x day(-1)); the third was given both CCl4 and candesartan cilexetil (8 mg x kg(-1) x day(-1)); fourth group was given 0.9% NaCl only. Seven weeks after initiating the treatment, indices of fibrosis were assessed. RESULTS: Candesartan cilexetil treatment significantly reduced the fibrosis development. These inhibitory effects were not observed in the captopril-treated group. The mean fibrosis score was significantly lower in the CCl4/candesartan group compared with the group applied to CCl4 alone and the group applied to CCl4/captopril. Similarly, the number of alpha-smooth muscle actin positive cells was markedly suppressed by candesartan treatment. CONCLUSIONS: The results suggest that AT-II plays a pivotal role in hepatic fibrogenesis and candesartan significantly attenuates the progression of liver fibrosis. This drug may provide an effective new strategy for prevention of liver fibrosis. Its effectiveness should be investigated in chronic liver disease associated with progressive fibrosis.

Actins↗
PubMed2003

Visual evoked potentials in multiple sclerosis before and after two years of interferon therapy.

Magnetic resonance imaging (MRI) is important in the diagnosis of and follow-up for the treatment of multiple sclerosis (MS); evoked potentials may be important if MRI is normal or cannot be performed. We assessed serial visual evoked potentials (VEPs) and cranial MRI in a group of clinically relapsing-remitting multiple sclerosis (N = 15) treated with interferon beta-lb (INFB-1b) and in normal subjects (N = 15). The investigations were done 1 week before INFB-lb therapy, 1 year later (N = 15), and 2 years later (N = 10). VEPs were abnormal in most of the patients; MRIs were abnormal in all patients. We used P100 latency as an electrophysiological index for the progress of illness. There were significant differences in VEPs between the beginning and ending of the interferon treatment. We concluded that VEPs would be a reliable index for following up the progress of MS under interferon therapy.

Adjuvants, Immunologic↗
PubMed2003

Partial regeneration/proliferation of the beta-cells in the islets of Langerhans by Nigella sativa L. in streptozotocin-induced diabetic rats.

This experiment was carried out to investigate the effect of N. sativa L. on histopathology of pancreatic beta-cells, and blood insulin and glucose concentrations in streptozotocin-induced diabetic rats. Fifty male Wistar rats (200-250 g) were divided into two experimental groups (diabetics with no treatment and diabetics with N. sativa L. treatment), each containing twenty-five rats. Diabetes was induced in both groups by a single intraperitoneal injection of streptozotocin (STZ) (50 mg/kg). The experimental animals in both groups became diabetic within 24 hours after the administration of STZ. The rats in N. sativa L.-treated group were given the daily intraperitoneal injection of 0.20 ml/kg of N. sativa L. volatile oil for 30 days starting the day after STZ injection. Control rats received only the same amount of normal saline solution. The rats in both groups received the last injection 24 hours before the sacrification and 5 randomly-selected rats in each group were sacrificed before, and the 1, 10, 20 and 30 days after the STZ injection to collect blood and pancreatic tissue samples. The N. sativa L. treatment caused a decrease in the elevated serum glucose, an increase in the lowered serum insulin concentrations and partial regeneration/ proliferation of pancreatic beta-cells in STZ-induced diabetic rats with the elapse of the experiment. It is concluded that the hypoglycaemic action of N. sativa L. could be partly due to amelioration in the beta-cells of pancreatic islets causing an increase in insulin secretion. More studies are needed to demonstrate the exact mechanism of action of N. sativa L. on ameliorated blood glucose concentration in STZ-induced diabetes.

Animals↗
PubMed2002

Cisplatin induces acute renal failure by impairing antioxidant system in guinea pigs: effects of antioxidant supplementation on the cisplatin nephrotoxicity.

This study aims to investigate the role of oxidants in cisplatin-induced nephrotoxicity. Cisplatin was administered intraperitoneally (i.p.) in a single dose (5 mg/kg) and guinea pigs were killed either after 24 h or 7 days. The same experiment was performed using animals treated with vitamins C and E combination and a natural antioxidant extract (SARMEX). The kidneys were then removed to be used in the analyses. Blood samples were also obtained from the animals to be used in routine biochemical assays. Twenty-four hours after treatment there was a significant decrease in the renal activities of total superoxide scavenger activity (TSSA), superoxide dismutase (SOD) and catalase (CAT) accompanied by a rise in malondialdehyde (MDA) levels. After 7 days, the fall in kidney enzymatic activities was far greater, while the increase in blood urea (BUN) and creatinine (CRE) was marked. Treatment with antioxidants causes significant increases in renal TSSA (7 day), non-enzymatic superoxide scavenger activity (NSSA) (24 h and 7 day) and SOD (7 day) activities, does not change glutathione peroxidase (GSH-Px) activity and decreases renal MDA (24 h and 7 day), blood BUN (7 day) and CRE (7 day) levels. Our results suggest that cisplatin treatment impairs both enzymatic and non-enzymatic antioxidant systems and causes peroxidation in the renal tissue, which leads to kidney failure. Antioxidant supplementation strengthens the renal antioxidant system, eliminates oxidation reactions, and prevents cisplatin-induced kidney failure.

Acute Kidney Injury↗
PubMed2002

Effects of topical mitomycin on inner ear: a light and electron microscopic study.

Providing maintenance of myringotomy patency without use of ventilation tubes in the treatment of secretory otitis media has been one of the important study areas. For this reason, laser and Mitomycin C (MMC) are used together in experimental studies. But there has been no ultrastructural studies concerning whether leakage of MMC to middle ear during application of this procedure has an ototoxic effect or not and if so, to what extent. In this study, we searched the ultrastructural changes which occurred in the middle ear by direct applications of MMC to the middle ear for different time durations. The study was carried out over thirty adult guinea pigs without ear diseases. Bilateral myringotomy was performed and MMC was applied only to the right middle ear of each guinea pig. The first group received MMC once for 10 minutes, the second group received it once for 20 minutes, and the third group took it each day for 10 minutes during a one week period. The left ears of the samples were accepted as the control group. On the 8th day, sacrification was carried out. After electron and light microscopy examination, significant changes in the inner ear were observed in the third group though no significant change was observed for the first and the second groups. As a result it was concluded that the application of MMC to the middle ear once for a short duration causes no toxic effect on the inner ear.

Administration, Topical↗