RESUMEN
Early childhood schizophrenia (COS) is a rare condition and has no established animal model to test new treatments. Previous studies have shown that repeated doses of 25â¯mg/kg ketamine produce schizophrenia-like changes in adult male Wistar rats, but adequate doses of ketamine in animal COS studies are not yet known. Male and female Wistar rats, 23 days old, received an injection of ketamine or intraperitoneal saline (i.p.) for 8 days. The animals underwent different behavioral tests: open field, social interaction, pre-pulse startle inhibition (PPI). Female rats showed behavioral changes at all ketamine doses (5, 15, 25 and 50â¯mg/kg), in contrast to males that only at 50â¯mg/kg dose had interrupted PPI and higher stereotypy in the open field test. The present study demonstrated that ketamine at a dose of 50â¯mg/kg once daily from 23 to 31 days postnatal reproduced changes similar to schizophrenia in pre-pubertal male and female Wistar rats and could be used, with other interventions, in future studies with animals in COS.