Biomedical subjects

Sibel Ozyazgan

Publications and source records attributed to Sibel Ozyazgan.

4 recordsLinked to original sources

PubMed2005

Effect of glucagon-like peptide-1(7-36) and exendin-4 on the vascular reactivity in streptozotocin/nicotinamide-induced diabetic rats.

We investigated the vascular effects of glucagon-like peptide-1 (GLP-1) and Exendin-4 in type 2 diabetic rat aortae. Studies were performed in a normal control group (NC) (0.2 ml i.p. saline, n = 10), streptozotocin (STZ)/nicotinamide diabetic control group (DC) (a single dose of 80 mg/kg STZ i.p. injection 15 min after administration of 230 mg/kg nicotinamide i.p.), GLP-1 (GLPC) control group (1 microg/kg twice daily i.p. for 1 month, n = 10), Exendin-4 control group (EXC) (0.1 microg/kg twice daily i.p. for 1 month, n = 10), GLP-1-treated diabetic group (GLPT) (1 microg/kg twice daily i.p. for 1 month, n = 10), and Exendin-4-treated diabetic group (EXT) (0.1 microg/kg twice daily i.p. for 1 month, n = 10). One month of GLP-1 and Exendin-4 treatment significantly decreased the blood glucose levels of diabetic rats (113 +/- 2 mg/dl, p < 0.001, and 117 +/- 1 mg/dl, p < 0.001, respectively versus 181 +/- 9 mg/dl in the DC group). Sensitivity (pD2) and maximum response (% Max. Relax) of acetylcholine-stimulated relaxations in the DC group (pD2: 6.73 +/- 0.12 and 55 +/- 6, respectively) were decreased compared with the non-diabetic NC group (pD2: 7.41 +/- 0.25, p < 0.05, and 87 +/- 4, p < 0.01). Treating diabetic rats with GLP-1, pD2 values and with Exendin-4, Max. Relax %values of aortic strips to acetylcholine returned to near non-diabetic NC values (pD2: 7.47 +/- 0.15, p < 0.05, and 87 +/- 3, p < 0.01, respectively). Maximal contractile responses (Emax) to noradrenaline in aortic strips from the diabetic DC group (341 +/- 27 mg tension/mg wet weight) were significantly decreased compared with the non-diabetic NC (540 +/- 66 mg tension/mg wet weight, p < 0.001) and the GLPT group (490 +/- 25 mg tension/mg wet weight, p < 0.05). There were no significant differences in pD2 values of aortic strips to noradrenaline from all groups. Emax to KCl in aortic strips from the DC group (247 +/- 10 mg tension/mg wet weight, p < 0.01) was significantly decreased compared with non-diabetic NC group (327 +/- 26 mg tension/mg wet weight). Treating diabetic rats with GLP-1 (GLPT), Emax values of aortic strips to KCl returned to near non-diabetic NC values (271 +/- 12 mg tension/mg wet weight). GLP-1 and (partially) Exendin-4 treatment could improve the increased blood glucose level and normalize the altered vascular tone in type 2 diabetic rats.

Animals↗

PubMed2004

What are the reactivities of coronary arteries harvested from the hearts exposed to cold ischemic preservation?

This study was designed to determine the effects of pretransplant ischemic hypothermic period on reactivities of major coronary arteries. Eleven pigs were used. Right, left anterior descending and circumflex coronary arteries harvested from 6 pigs following single dose of cardioplegia and cardiectomy. The same procedures were performed in 5 pigs after 6 hours static 4 degrees C hypothermic preservation of the hearts. Strips prepared from these 3 coronary arteries were placed in organ chambers and contractions with acetylcholine and histamine and KCL and dilatations with noradrenaline following submaximal contractions with acetylcholine and histamine were documented. There was no statistically significant difference between results taken from both groups. The pretransplant period (until 6 hours) does not cause important differences on the reactivities of coronary arteries.

Acetylcholine↗

PubMed2003

Role of bombesin and cholecystokinin receptors in gastric injury induced by hemorrhagic shock in the rat.

Bombesin has been shown to have trophic effects on the gastrointestinal tissue. Bombesin has direct mitogenic effects besides stimulating release of gastric hormones. The aim of this study was to investigate the effect of bombesin in hemorrhagic shock-induced stress ulcers in rats, and the role of cholecystokinin (CCK) receptors in this activity. Hemorrhagic shock was created by withdrawing 3 ml blood/200 g b.w. of rats. At the end of the 1-hour hypovolemic shock period, histological analysis, gastric ulcer index, gastric myeloperoxidase activity and gastric protein oxidation levels were determined. When given before the hemorrhage, subcutaneous bombesin (10 microg/kg) reduced macroscopically gastric ulcer index (p < 0.05). Blockade of CCK-A receptors with intraperitoneal MK-329 (1 mg/kg) did not reverse bombesin-induced gastroprotection. Blockade of CCK-B receptors with intraperitoneal L-365,260 (25 mg/kg) reversed bombesin-induced gastroprotection. Blockade of the two receptors resulted in no gastroprotection at all. It is concluded that bombesin treatment attenuated hemorrhagic shock-induced stress ulcers in rats via CCK receptors.

Animals↗

PubMed2003

Low-cost antibiotic loaded systems for developing countries.

Treatment of osteomyelitis with local antibiotic delivery systems has become a common practice in orthopaedic surgery. This study attempted to show that locally produced pure or bioglass reinforced plaster of Paris, hydroxyapatite and sodium alginate are promising biomaterials and mainly because of economical reasons and availability, may be an alternative in clinical practice, especially for developing countries. A total of 32 rabbits were divided into four groups (n:8). In group A, sodium alginate + cephazoline; in group B, plaster of Paris + bioglass + cephazoline; in group C, plaster of Paris + hydroxyapatite + cephazoline and in group D, plaster of Paris + cephazoline were used. The blood serum cephazoline concentrations were analyzed by high performance liquid chromatography on days 1 to 10 everyday and then at days 13, 17, 18, 24, 25 and 30. The mean values +/- standard deviations and median values of blood serum antibiotic concentrations for groups A, B, C and D were 1.45 +/- 0.40 (1.42) mcg/ml, 1.53 +/- 0.64 (1.31) mcg/ml, 1.92 +/- 0.39 mcg/ml (1.90) and 1.41 +/- 0.65 (1.25) mcg/ml, respectively. The detected antibiotic level was constantly over the minimum inhibitory concentration for Staphylococcus aureus. In conclusion, it can be stated that these materials are promising as a antibiotic delivery system even with simple production methods.

Alginates↗