Lew ssnhsd

2.5–3.0 month-old male Lewis (LEW/SsNHsd) inbred rats (Envigo Ltd, Rehovot, Israel) were used in all experiments. The experiments were approved by the Tel Aviv University Animal Care and Use Committee. The rats were maintained on a regular 12-hr dark/light cycle with access to food and water ad libitum. Standard chow diet was from Envigo Ltd. The animals were divided into three groups, as follows: 1) intact rats (N = 9); 2) rats exposed to icv-STZ and two months later to subarachnoid grafting of pancreatic islets suspended in the vehicle (STZ-islets rats) (N = 7); and 3) rats exposed to icv administration of streptozotocin (icv-STZ) and two months later to subarachnoid administration of a vehicle (Hank's Balanced Salt Solution, HBSS) only (STZ-sham rats) (N = 4). Two and six months after the islet grafting, cognitive functioning was studied by Morris water maze (MWM) test. At the end of experiments, overdose of carbon dioxide was used for euthanasia. The brains were removed and analyzed by histological and biochemical methods. In all assays, the assessors were blind to the group status (experimental versus control) of the rats.