Amphetamine-induced psychosis is frequently associated with a chronic, high
-dose, daily pattern of amphetamine exposure. In the present study we inves
tigate the effects of prenatal exposure to amphetamine during the developme
nt of the central noradrenergic (NA) system in adult rats. Pregnant Wistar
rats were given 4 mg/kg/day of D-amphetamine (AMPH), subcutaneously, from g
estational day 8 to 21. No additional drug treatment was given to the anima
ls until the beginning of the experiments, in adult, control and prenatally
amphetamine treated rats. Since we study the electrophysiology and neuroch
emistry of the central NA system, we investigated the electric activity of
locus coeruleus (LC) norepinephrine (NE) neurons and the levels of ME on pr
efrontal cortex. What we found, was a decreased number of spontaneously act
ive cells in the LC nucleus with a lower pattern of discharge whereas, the
basal levels of NE in the prefrontal cortex, was greatly increased. The inc
reased cortical NE levels, observed in the present study may account for th
e proposed hyperactive NA system being responsible for some psychotic sympt
oms observed in paranoid schizophrenia. Besides, our results concerning the
permanent alteration observed in the central NA system, in rats prenatally
exposed to amphetamine, raise the possibility that this animal model may b
e useful to further study the neurobiologic alterations underlying certain
clinical features involved in some psychosis such as schizophrenia. (C) 199
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