Gl. Florant et al., THE EFFECT OF A LOW ESSENTIAL FATTY-ACID DIET ON HIBERNATION IN MARMOTS, The American journal of physiology, 264(4), 1993, pp. 747-753
We investigated the effect of an essential fatty acid (EFA)-deficient
diet on hibernation patterns in yellow-bellied marmots (Marmota flaviv
entris). Fatty acid (FA) analysis of white adipose tissue (WAT) from a
nimals maintained for 2 mo on the EFA-deficient diet suggested that li
ttle or no EFAs were present in the gonadal or omental fat depots. Hib
ernation bout lengths of the EFA-deficient animals were significantly
shorter (P < 0.01) than control animals. Stated another way, these ani
mals aroused twice as frequently compared with control animals and use
d more energy to survive winter. Analysis of WAT composition and blood
samples revealed that animals were highly lipolytic during winter. Fu
rthermore, the release of FAs was not random: linoleate (cis-9,cis-12-
octadecadienoic acid; 18:2, a diene EFA) was significantly (P < 0.05)
under-represented in venous outflow from the gonadal WAT pad based on
the percentage of this species in WAT. The concentration of saturated
FAs was higher than that predicted from the WAT-FA composition. We con
clude that linoleate is preferrentially retained within WAT and that c
oncentrations of this EFA may influence hibernation behavior. Thus EFA
s may have a thermoregulatory role in hibernation in addition to their
role as essential precursors for physiologically important lipids aft
er hibernation is over.