Sprague Dawley Strain Case Study

Materials and Methods

Experimental Design

Forty (40) male albino rats of sprague Dawley Strain weighing (180 - 200 g) were included in the present study. The rats were obtained from the Laboratory of Animal Colony, Minya, Egypt and were housed in well aerated cages under hygienic condition and were provided commercial rodent diet and water ad libitum for one week for adaptation. Rats were housed in temperature controlled rooms (25°C) with constant humidity and 12h/12h light/dark cycle. After the adaptation period, the rats were divided into five groups (n=8 in each group) as follows:

Group 1 (G1): considered as normal control group in which rats were fed on balanced diet for six weeks.

Group 2 (G2): served as positive control group in which

Rats were fed on high fat diet and received (12 mg/kg) of orlistat daily dissolved in saline (1ml/kg) by intraperitoneal injection (Calderon et al., 2011) for six weeks.

Group 4 (G4): represented the group that was treated with amphetamine. The animals received high fat diet and amphetamine in a dose of (1.5 mg/kg) daily dissolved in saline (1ml/kg) by intraperitoneal injection (Geigera et al., 2009) for six

Animals were also weight immediately prior to sacrifice (fasted body weight). Animals were sacrificed under anesthesia with diethyl ether, and then blood samples were immediately collected in clean and dried Wiesserman tubes from the portal vein. First part of blood was collected in tubes containing potassium oxalate and sodium fluoride for the estimation of plasma glucose by O-toluidine method of Sasaki et al. (1972). Second part of blood was left to coagulate then centrifuged at 3000 rpm for 15 minutes to obtain serum to estimate some biochemical parameters. Serum insulin and leptin were estimated according to the methods of Wilson and Miles, (1977) and Palacio et al. (2002) respectively. (TG) and high density lipoprotein cholesterol (HDL-c) were determined by using enzymatic colorimetric methods described by Kostener et al. (1977). Low density lipoprotein cholesterol (LDL-c) was calculated according to the method of (Fruchart et al. (1982). Serum alanine and aspartate aminotransferase (ALT&AST) activities were estimated according to the method of (Reitman and Frankel, 1957). Blood superoxide dismutase (SOD) and catalase (CAT) were estimated according to the method of (Flohe and Gunzler., 1984). Lipid peroxides values were determined with spectrophotometric measurement of the amount of malondialdehyde (MDA) equivalents with thiobarbituric acid and was expressed as