Effect of diazepam binding inhibitor (DBI) on the fluid intake, preferenceand the taste reactivity in mice

We have reported that a diazepam binding inhibitor (DBI)-like peptide is re leased by the aversive quinine stimuli 'Chem. Senses 25 (2000) 739'. To det ermine the effect of DBI on the fluid intake, we injected a DBI peptide fra gment into the fourth ventricle in mice, DBI suppressed the intake of 5% su crose, water and 0.9 mM quinine-HC1 and the preference for 0.05% saccharin. Administration (i.p.) Of flumazenil, a benzodiazepine receptor antagonist, 20 min before the injection of DBI (i.c.v.) antagonized the suppressive ef fect of DBI on the intake and the preference for saccharin. We also studied the dose dependency of the effect of DBI on the intake of 5% sucrose. Inje ction of DBI in excess of 3 mug suppressed the intake of 5% sucrose in mice . Furthermore, injection of DBI (i.c.v.) increased the aversive response to 0.9% NaCl in the taste reactivity in mice. These results suggest that DBI affect the preference to food. (C) 2001 Elsevier Science B.V. All rights re served.