Neuroprotective effects of selenium and ginkgo biloba extract [EGb761] against ischemia and reperfusion injury in rat brain

To determine the neuroprotective effects of Ginkgo biloba extract [EGb761] and Selenium [Se], and the combination of these agents on ischemia/reperfusion [I/R] injury in a rat model of transient global cerebral I/R. This experimental study took place in the Animal Research Laboratory at Dokuz Eylul University, Izmir, Turkey in the year 2006. Fifty rats were subjected to cerebral I/R induced by right carotid artery occlusion technique for a duration of 45 minutes, and then were treated with EGb761 [50 mg/kg/day, ip] and Se [0.625 mg/kg, ip], alone or in combination for 14 days after surgery. Superoxide dismutase, and glutathione peroxidase activities were measured in the hippocampal tissues from 25 animals. Histopathological examinations were also carried out under light and electron microscopy from the rest of animals. The results suggest that EGb761 has a potent neuroprotective effect against cerebral I/R induced injury in rat brain that is comparable with that of Se. However, the combined use of EGb761 and Se does not further protect from neuronal injury when compared with the use of both agents alone. Our results suggest that administration of EGb761, Se and its combination with EGb761 have significant neuroprotective effects on I/R injury in rats via suppression of oxidative stress

comparative study of the ultrastructure of submandibular, parotid and exocrine pancreas in diabetes and fasting

To comparatively analyze the ultrastructural changes in the submandibular and parotid glands and in the exocrine pancreas following diabetes induced by Streptozotocin exposure and the effects of fasting and insulin treatment on these alterations. For experimental procedure, we included 48 Sprague-Dawley type rats in July 2001-March 2002 at Gazi University, Turkey. We divided the rats into 8 groups following the infusion of Streptozotocin. While the degeneration manifested itself as accumulation of secretions within the mucous cells in the submandibular gland, lipid droplets were absent, being replaced by vacuolar structures. The parotid gland and exocrine pancreas, having similar properties, were affected similarly. Diabetes-induced loss of granules was observed in the serous cells in both glands. There was diffuse lipid accumulation within these cells. Regarding granule content, we observed the most prominent degenerative changes in the parotid gland. While cellular loss was observed in neither the submandibular, nor the parotid gland, we noted presence of apoptotic cells was noted in the pancreas. State of fasting was found to cause alterations within the glands indicating increased activity. While insulin treatment was seen to restore the structure to normal in general in both of the 3 glands. This study demonstrated that both of the 3 glands are affected by diabetes and concomitant fasting, and this effect manifests itself via the granule content