Metabolic consequence of congenital asplenia caused by the Dominant hemimelia mutation in mice.

The potential roles of the spleen in lipid metabolism have been debated for the last 2 decades. Although there are some discrepancies among investigations, they are in agreement on the point that the spleen has roles in lipid metabolism. In the present study, role of the spleen in lipid metabolism was investigated by use of a hereditary asplenic mouse strain carrying a Dominant hemimelia (Dh) mutation. In studies on females, asplenic mice (Dh/+) had significantly lower plasma high-density lipoprotein-cholesterol (HDL-CHO) levels than did eusplenic mice (+/+) on a chow diet. On a high-fat diet, Dh/+ had significantly higher HDL-CHO than did +/+. In studies on Y-consomic strains (DH-Chr Y), DH-Chr Y-Dh/+ had significantly lower values than did DH-Chr Y-+/+ for all traits. For body weight and HDL-CHO, there were significant differences in mean trait values among DH-Chr Y-+/+, suggesting that Y-linked genes affect these traits. Furthermore, pattern of distribution of mean trait values among Y-consomic strains largely differed between DH-Chr Y-+/+ and DH-Chr Y-Dh/+, suggesting the presence of interaction between Dh and Y-linked genes. The present study shows that Dh has effects on lipid metabolism. Although Dh has multiple phenotypic effects it is possible that the change in lipid levels is affected in part by the absence of the spleen.