Diabetes simulating insulin dependence (type
1 diabetes) was induced by intraperitoneal injection
of streptozotocin (STZ, 55 mg/kg body weight,
Sigma, USA) to adult male Sprague-Dawley rats.
After two weeks, rats with a nonfasting blood
glucose over 200 mg/dl were included in the
experiment (Rakeiten et al., 1963). Non insulin
dependent diabetes (type 2 diabetes) was induced
by intraperitoneal injection of STZ 90 mg/kg body
weight to 48-hour old pups of Sprague-Dawley rats
(Bonner-Weir et al., 1981). At 8 weeks old, the
rats with nonfasting blood glucose more than 200
mg/dl were used in the study. The rats used in this
experiment were obtained from the Experimental
Animal Unit of the Faculty of Medicine, Khon Kaen
University. All animal experiments were conducted
in accordance with the general guidelines for the
care and use of laboratory animals.