Age, sex and source of hamster affect experimental cholesterol cholelithiasis

Abstract

In the present study, we examined the effect of the following factors on a hamster model of cholesterol cholelithiasis: (i) the source of the golden Syrian hamsters (Sasco, Omaha, NE or Charles River, Wilmington, MA), (ii) the sex of the experimental animals and (iii) their age (4 wk vs. 8 wk of age). All hamsters were fed a semipurified diet which contained cholesterol (0.3%) and palmitic acid (1.2%). No cholesterol gallstones formed in any of the female hamsters regardless of age or source. The 4-week-old male hamsters from Sasco had the greatest incidence of gallstones (93%). The 8-week-old male hamsters tended to have a lower incidence of cholesterol gallstones than the younger ones, regardless of the commercial supplier (67 vs. 93% for Sasco and 27 vs. 40% for Charles River). Female hamsters had higher liver and serum cholesterol levels than the male hamsters; Charles River hamsters had lower serum cholesterol concentrations than the Sasco animals. Total biliary lipid concentrations were highest in Sasco male hamsters, but biliary cholesterol (mol%) was lower in the males than in the females (4.2-4.5% vs. 6.1-7.1%) regardless of age. The cholesterol saturation indices were higher in the Sasco females than the corresponding males; these values were lower in the Sasco hamsters than the Charles River animals, regardless of age or sex. The male Sasco hamsters had a higher total biliary bile acid concentration (98.9 mg/mL) than the Sasco females (58.9 mg/mL) and the Charles River animals (24.6 mg/mL for males and 38.2 mg/mL for females). The percentage of chenodeoxycholic acid in bile was significantly lower, and the percentage of cholic acid was higher in all females as compared to males.(ABSTRACT TRUNCATED AT 250 WORDS)

Alteration of sphingolipid metabolism and pSTAT3 expression by dietary cholesterol in the gallbladder of hamsters

“…(original magnification, X400) Bar = 1 mm. equally susceptible to cholesterol gallstone formation, presumably due to differences in cholesterol and bile acid metabolism (Ayyad et al, 1993). The consumption of cholesterol-enriched diets leads to increased plasma cholesterol concentrations in most animal species, including humans, but the degree of the responsiveness differs according to the species and the individuals within a species (Chen et al, 1998).…”

The Experimental Use of Syrian Hamsters

“…The Syrian hamster displays significant gender differences in the basal rate of hepatic sterol synthesis which is several-fold higher in females fed a regular chow diet as compared to age-matched males on the same diet (Spady et al, 1983). In contrast to humans, female hamsters are less susceptible to gallstones because they maintain more favorable biliary lipid and bile acid profiles (predominantly glycocholate) characterized by lower molar percentages of cholesterol and chenodeoxycholate (Ayyad et al, 1993;Trautwein et al, 1999). Dietary administration of androgens to female hamsters on a lithogenic diet (0.3% cholesterol) induces cholesterol gallstones at a comparable rate to induction in males fed a similar diet.…”

Distribution of cholesterol among its carriers in the bile of male and female hamsters

“…A hamster model of cholesterol cholelithiasis has been in use in our laboratory for a number of years (10)(11)(12)(13)(14)(15)(16). Lithogenesis in this model is a function of several factors, particularly of dietary constituents and source, age and sex of the experimental animals (11,(14)(15)(16).…”

“…A hamster model of cholesterol cholelithiasis has been in use in our laboratory for a number of years (10)(11)(12)(13)(14)(15)(16). Lithogenesis in this model is a function of several factors, particularly of dietary constituents and source, age and sex of the experimental animals (11,(14)(15)(16). Recently, we reported that under standard conditions (lithogenic diet fed for six weeks) gallstones were formed in male hamsters but not in female hamsters of either the Sasco (Sasco Inc., Omaha, NE) or Charles River (Charles River Laboratories, Wilmington, MA) "strains" (16).…”

“…Lithogenesis in this model is a function of several factors, particularly of dietary constituents and source, age and sex of the experimental animals (11,(14)(15)(16). Recently, we reported that under standard conditions (lithogenic diet fed for six weeks) gallstones were formed in male hamsters but not in female hamsters of either the Sasco (Sasco Inc., Omaha, NE) or Charles River (Charles River Laboratories, Wilmington, MA) "strains" (16). We hypothesized that lithogenesis might occur more rapidly in mate hamsters as compared to female hamsters after a six-week feeding if (i) the bile of the former contains biliary cholesterol in the form of vesicles, and (ii) in the males, the vesicular cholesterol/phospholipid ratio is relatively higher than in females.…”