Journal of Research in Medical Sciences1735-1995632001090134173417ENPhysiology Dept, School of Medicine, Isfahan University of Medical Sciences and Health Services, Isfahan, Iran2001090120090411<font><font color="#555555"><span style="font-size: 10pt; font-family: Tahoma">Introduction. Various factors affect on the incidence of atherosclerosis, that most important of them is the high plasma concentration of cholestrol in the form of low density lipoproteins (LDL). This study evaluated the effect of leptin (the product of the ob gene) on the cholesterol, triglyceride, LDL and HDL plasma level. Fatty streak induced hypercholestrolemia in rabbit was studied.<br />Methods. Rabbits were divided to six groups and feeded as followed. Group one: regular diet, 2nd group: high cholestrol diet (HCD), 3rd group: regular diet +leptin 0.1 mg/kg/day, 4th group: HCD + leptin 0.1 mg/kg/day, 5th group: HCD+leptin 1 mg/kg/day and 6th group: HCD+leptin 10 mg/kg/day. Blood samples were taken before and after the study and the plasma level of cholestrol, triglycerid, LDL, HOL and blood pressure was measured. Arterial wall was histopathologically on aorta.<br />Results. The plasma level of cholestrol, triglycerid, LDL, HDL in all HCD group showed significant increasing. LDL between 4th and 6th group had no difference (P > 0.05). Fatty steaks in all HCD groups were equal.<br />Discussion. According to the results, we suggest that doses of 0.1, 1 and 10 mg/kg/day of leptin in a short period (30 day), increase the plasma level of LDL, but it have not any effect on the mean blood pressure, plasma level of cholesterol, triglycerid and HDL in rabbit.</span></font></font>http://jrms.mui.ac.ir/index.php/jrms/article/view/3417