title: Species differences in blood serum reserves for cholesterol solubilization.
abstract: The capacity of male human, rat, and guinea pig sera to solubilize cholesterol was measured by in vitro equilibration. Evaporation, adsorption by filter paper and/or cholesterol, and protein denaturation were controlled by measuring serum protein and albumin along with cholesterol contents. The uptake of cholesterol for the above groups was 23.1 +/- 1.2, 18.9 +/- 1.8, and 10.7 +/- 0.8 mg/100 ml, respectively. The percentage increases over initial serum cholesterol were 11.9 +/- 0.9, 18.7 +/- 2.0, and 35.1 +/- 2.7%, respectively. The uptake of cholesterol by serum per se without involvement of either releasing or target tissues appears to be an irreversible and protective solubility phenomenon; no cholesterol plates were deposited upon the undissolved solute or precipitated on addition of triglyceride to cholesterol-saturated serum. The omnivorous human and rat had a greater absolute reserve for solubilizing cholesterol, but the herbivorous guinea pig a greatly enhanced relative (% increase) reserve.
mesh_terms: D000818:Animals; D001793:Blood Preservation; D002784:Cholesterol / Q000097:blood*; D003327:Coronary Disease / Q000097:blood; D005374:Filtration; D006168:Guinea Pigs; D006801:Humans; D007674:Kidney Diseases / Q000097:blood; D051381:Rats; D012995:Solubility; D013045:Species Specificity
chemical_list: D002784:Cholesterol