ABSTRACT
The present study was performed to compare glucocorticoid levels in obese KKA (y) and ob/ob mice with those in normal C57BL/6J mice, and the effect of high-fat diet on glucocorticoids in KKA (y) and ob/ob mice. Liver, mesenteric and epididymal adipose tissue corticosterone and 11-dehydrocorticosterone concentrations as well as circulating corticosterone concentrations were measured. The KKA (y) and ob/ob mice displayed elevated serum corticosterone levels compared to normal mice, 2.0 to 2.8-fold in KKA (y), and 11 to 16-fold in ob/ob mice. Liver corticosterone levels were 3.0 to 5.1 and 6.2 to 8.1-fold, and 11-dehydrocorticosterone levels were 3.4 to 3.6 and 6.7 to 8.2-fold higher in KKA (y) and ob/ob mice compared to normal mice. Mesenteric adipose tissue corticosterone levels were 2.7 to 4.2-fold higher, and 11-dehydrocorticosterone levels were 2 to 4-fold higher in ob/ob than in KKA (y) mice. Epididymal adipose tissue corticosterone levels were 3.0 to 6.2-fold higher, and 11-dehydrocorticosterone levels were 1.8 to 2.0-fold higher in ob/ob than in KKA (y) mice. Circulating, hepatic, and mesenteric and epididymal adipose tissue glucocorticoid concentrations were low in the normal C57BL/6J mouse, high in the ob/ob mouse, and intermediate in the KKA (y) mouse. 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1) mRNA levels were doubled in ob/ ob compared to KKA (y) mice in all three tissues. Glucocorticoid concentrations correlated with 11beta-HSD1 mRNA levels. High-fat diet had no effect on the tissue glucocorticoid concentrations.