Ovariectomized hamster: A potential model of postmenopausal hypercholesterolemia

A suitable and economical animal model of ovarian hormone deficiency can gr eatly enhance the understanding of postmenopausal-elevated risk of coronary heart disease, The male Golden Syrian hamster is a well-established small animal model of hypercholesterolemia, but the effect of ovariectomy on lipi d profile in the female hamster is unclear The objective of this study was to determine whether ovariectomized hamsters develop hypercholesterolemia a nd experience changes in body fat distribution consistent with changes obse rved in postmenopausal women. Twenty-two 90-day-old female Golden Syrian ha msters were divided into two groups and lipids either ovariectomized or sha m-operated and given free access to a standard cholesterol-free laboratory diet for 65 days. Ovariectomized hamsters had significantly (P < 0.05) elev ated serum total cholesterol concentrations (16.6%) as well as abdominal fa t mass (56%; P<0.01) despite equal food intake compared,with the sham-opera ted group. In contrast, the mean intestinal weight and in vivo rare of ster ol biosynthesis ct were significantly (P < 0.002 and P = 0.01, respectively ) lower in the ovariectomized compared with the sham-operated group. In viv o rates of hepatic sterol biosynthesis were directionally lower (P = 0.1) i n the ovariectomized group. No significant differences were observed in fin al body weight, serum triglycerides, or liver total cholesterol and lipids between the two groups. In conclusion, ovariectomized hamsters undergo chan ges in serum cholesterol and fat distribution similar to those experienced by postmenopausal women, and thus may serve as an appropriate model for pos tmenopausal hypercholesterolemia. (C) Elsevier Science inc. 1999, All right s reserved.