The effects of adulthood olanzapine treatment on cognitive performance and neurotrophic factor content in male and female rats neonatally treated with quinpirole.

Male and female Sprague-Dawley rats were administered quinpirole (1 mg/kg, i.p.) or saline once daily from postnatal day (P)1 to P21.

The effects of eticlopride on Morris water task performance in male and female rats neonatally treated with quinpirole.

Rationale: Previous studies have shown that neonatal quinpirole treatment which results in long-term dopamine D2 receptor supersensitization (D2 receptor priming) produces cognitive deficits in preweanling and adult rats behaviorally tested on the Morris water task (MWT).

Objective: This study was designed to analyze whether pretraining administration of the D2 antagonist eticlopride alleviates cognitive deficits produced by neonatal quinpirole treatment.

Methods: Both male and female Sprague-Dawley rats were treated with quinpirole HCl (1 mg/kg) or saline from postnatal days 1 to 21.

Neonatal quinpirole treatment impairs Morris water task performance in early postweanling rats: relationship to increases in corticosterone and decreases in neurotrophic factors.

Background: Past studies from this laboratory have shown that quinpirole administration from postnatal day (P) 1-21 produces persistent supersensitization of the dopamine D2 receptor that persists throughout the animal's lifetime.

Methods: In Experiment 1, both male and female rats were treated with quinpirole or saline from P1-21 and tested on the place and match-to-place versions of the Morris water task (MWT) from P22-28. In Experiment 2, both male and female rats were administered either acute or chronic injections of quinpirole (1 mg/kg) or saline beginning on P1 until analysis for corticosterone (CORT) on P7, 14, or 21.

Adulthood nicotine treatment alleviates behavioural impairments in rats neonatally treated with quinpirole: possible roles of acetylcholine function and neurotrophic factor expression.

Increases in dopamine D(2) receptor sensitivity are known to be common in drug abuse and neurological disorders. Past data from this laboratory have shown that long-term increases in D(2) sensitivity can be produced by quinpirole treatment (a D(2)/D(3) agonist) during early development. The present investigation was designed to test the hypothesis that nicotine administration in adulthood would reduce both cognitive and skilled reaching impairments produced by increases in D(2) sensitivity.