The Syrian golden hamster is a frequently used model to study
cholesterol and
bile acid metabolism as well as
cholesterol-induced
cholelithiasis. However, diet-induced
gallstones seem limited to young male hamsters of certain strains that develop depressed
cholate/
chenodeoxycholate bile acid ratios. To further elucidate gender and age specific aspects of
cholesterol and
bile acid metabolism, i.e. a possible age-related
bile acid/
gallstone relationship, plasma and biliary
lipids and
bile acid composition were analyzed in male and female hamsters under various physiological conditions of age and diet, the latter formulated with and without
dietary cholesterol. During normal development (no
cholesterol challenge) the percentage of
cholic acid decreased while
chenodeoxycholate increased, the shift being more pronounced in males. Furthermore, female hamsters had higher total plasma
cholesterol than in males, while hepatic and biliary
lipids did not differ. When challenged with excessive
dietary cholesterol, female hamsters again developed significantly higher total plasma and hepatic
cholesterol concentrations. Biliary
lipids and
cholesterol gallstone incidence revealed a significant gender effect with male hamsters developing a higher lithogenic index and more
gallstones (
cholesterol and pigment stones) than females. Female hamsters revealed a lower percentage of
chenodeoxycholate and a higher percentage of
cholate resulting in a more protective, higher
cholate/cheno ratio (1.5 +/- 1.0) than in males (1.0 +/- 0.2). In summary, the
bile acid pattern in developing and
cholesterol-fed hamsters renders females less susceptible to
gallstones, in part because they maintain more favorable biliary
lipid and
bile acid profiles, characterized by lower molar percentages of biliary
cholesterol and
chenodeoxycholate.