Increased schedule-induced polydipsia in the rat following subchronic treatment with MK-801.
Primary polydipsia, defined as excessive fluid intake not explained by medical causes, has been reported to occur in over 20% of chronically ill psychiatric inpatients and is especially common in schizophrenic populations. We tested the hypothesis that in an animal model of schizophrenia-like symptoms (subchronic injections of MK-801, 0.5 mg/kg twice daily for 7 days) an increase in the acquisition of schedule-induced polydipsia (SIP) will occur. Young adult, male rats acquired SIP when food-restricted and placed on a non-contingent fixed-time 1-min food schedule. In comparison with saline-treated control animals, subchronic MK-801 treatment significantly increased SIP. These findings suggest an animal model of polydipsia associated with schizophrenia in humans.
Hawken
Emily R
ER
Centre for Neuroscience Studies, Queen's University, Kingston, ON K7L 3N6, Canada.
Delva
Nicholas J
NJ
Reynolds
James N
JN
Beninger
Richard J
RJ
D000704:Analysis of Variance; D000818:Animals; D003216:Conditioning, Operant / Q000187:drug effects / Q000502:physiology; D016291:Dizocilpine Maleate / Q000494:pharmacology*; D004326:Drinking / Q000187:drug effects*; D004327:Drinking Behavior / Q000187:drug effects*; D004334:Drug Administration Schedule; D008297:Male; D018696:Neuroprotective Agents / Q000494:pharmacology*; D051381:Rats; D012055:Reinforcement Schedule; D013894:Thirst / Q000187:drug effects*; D013997:Time Factors
D018696:Neuroprotective Agents; D016291:Dizocilpine Maleate