The cholecystokinin-like peptide, ceruletide, reduces isolation-induced aggression in mice

Ceruletide, a non-mammalian decapeptide related to cholecystokinin octapeptide, reduced the aggressiveness of isolated NMRI mice. In this respect, its ED50 (mumol/kg, s.c.) was 0.024 (95% confidence range, 0.0133-0.0447) and that of haloperidol 3.38 (1.488-7.669). An approximately equipotent dose of diazepam was 17.5 mumol/kg.