Baseline temperature in an animal model of schizophrenia: long-term effects of perinatal phencyclidine administration

Phencyclidine (PCP), a dissociative anaesthetic, acts as a noncompetitive N-methyl-d-aspartate (NMDA) receptor antagonist. PCP is a psychostimulant capable of producing both positive and negative symptoms of schizophrenia, including cognitive dysfunction in normal humans. Perinatal phencyclidine administration to rats has been widely accepted as an animal model of schizophrenia. It has been known for a long time that schizophrenia patients may develop various thermoregulatory disturbances. The aim of this study was to assess the acute effects of phencyclidine administration on the temperature of newborn rats, the long-term effects on the baseline temperature of perinatal phencyclidine administration and the effects of a PCP challenge on the temperature of adult perinatally treated rats. The animals were treated on the 2nd, 6th, 9th and 12th postnatal (PN) days with either phencyclidine (10 mg/kg) or saline. The interscapular skin temperature was measured during the first 40 postnatal days and subsequently the colonic temperature until PN day 62. The immediate effect of phencyclidine administration to pups was a significant decrease of the body temperature, while the application of PCP to adult rats perinatally treated with either saline or PCP caused a significant increase of the baseline temperature. Perinatal phencyclidine administration to rat pups produced a long lasting effect on the baseline temperature. It can be concluded that the nature of the response to acute phencyclidine administration differs between newborn and adult rats. Further experiments are necessary in order to clarify the role of specific neurotransmitter systems in the changes of temperature regulation provoked by phencyclidine administration.