Reduced epinephrine-stimulated lipolytic activity in male golden-mantled ground squirrel during hibernation: an in situ microdialysis study

We studied lipolytic activities in vivo in golden mantle ground squirrels d uring pre-hibernation and hibernation using microdialysis technique. Microd ialysis probes were inserted into the abdominal subcutaneous adipose tissue s. Baseline lipolysis were assessed by measuring glycerol concentration. Ep inephrine-stimulated lipolysis was also examined. Eight squirrels (four mal e, four female) were studied in each of the two stages. Basal glycerol conc entrations were lower in the hibernating state than in the pre-hibernation stale in male squirrels (P < 0.05). Epinephrine application induced glycero l release in male and female squirrels (P < 0.001) in both stages. Male squ irrels demonstrated a reduced epinephrine-stimulated glycerol release in th e hibernating state, which was not observed in female squirrels. (C) 1999 E lsevier Science Inc. All rights reserved.