Neuropeptide Y gene expression in the jerboa arcuate nucleus: modulation by food deprivation and relationship with hibernation

Using in situ hybridization, the mRNA levels encoding neuropeptide Y (NPY) was investigated in the arcuate nucleus (ARC) of jerboas under three differ ent states of energy balance. (1) normally feeding animals, (2) hibernating animals and finally (3) animals food deprived for 5 days. The hibernating and food deprived jerboas exhibited a significant increase (130%; P < 0.05 and 210%; P < 0.01, respectively) of mRNA expression as compared with contr ols. This elevated NPY mRNA expression supports the hypothesis that NPY may be implicated in abnormal feeding behaviour associated with eating depriva tion. The stimulation of NPY gene expression in hibernating jerboas may be related to food deprivation and / or cold exposure since NPY is known to be a hypothermiant factor. It is thus envisaged that NPY with in neurons of t he ARC plays an integrative role in the control of energy metabolism. (C) 2 001 Published by Elsevier Science Ireland Ltd.