Impaired lipolysis in RXRαadL−/− mice during
fasting. (A) Fasted RXRαadL−/− mice
suffer from hypothermia. Rectal temperature was determined on
10-week-old CT and RXRαadL−/− (KO) mice at the
beginning of the light cycle (fed state) and after a 1- or 2-day fast
that was started at the beginning of the light cycle. (Error bars,
SEM.) *, P < 0.05; **,
P < 0.001. (B) Gross appearance of
epididymal fat pad after fasting. Testes and epididymal fat pads from
3-month-old CT and RXRαadL−/− (KO) mice after a 2-day
fast are presented. (C) Histological analysis of
epididymal fat pad. Sections of the epididymal fat pads shown in
B were stained with Oil red O. (Scale bar, 20 μm.)
(D) Weight of epididymal fat pad. Epididymal fat pad
weight of fed and fasted (2 days) 10-week-old CT and KO mice was
measured. Values are expressed as the mean ± SEM
(n = 9–10). **,
P < 0.001; ***,
P < 0.0001. (E) Plasma FFA
concentrations. FFA was determined in 10-week-old fed and fasted (1 and
2 days) CT and KO mice. Values are expressed as the mean ± SEM
(n = 9–10). # indicates values below background
levels (dashed line, 0.1 mmol/liter).