I. Vathy et al., MODULATION OF CATECHOLAMINE TURNOVER RATE IN BRAIN-REGIONS OF RATS EXPOSED PRENATALLY TO MORPHINE, Brain research, 662(1-2), 1994, pp. 209-215
The concentration and turnover rate of brain catecholamines were measu
red in the hypothalamus, preoptic area (POA), frontal cortex, striatum
and cerebellum of adult male and female rats exposed in utero to morp
hine (5-10 mg/kg/twice a day) during gestation days 11-18. Norepinephr
ine (NE) and dopamine (DA) turnover rates were estimated following alp
ha-methyl-paratyrosine (AMPT) administration. Prenatal morphine altere
d NE content and turnover in male and female rats in a regionally spec
ific, sexually dimorphic manner. Basal NE content increased approximat
ely 60% in the hypothalamus of male rats, but it decreased about 30% i
n the hypothalamus of female rats. NE turnover in the hypothalamus of
morphine-exposed rats increased 50% in males and decreased 50% in fema
les. Prenatal morphine had no effects on NE turnover in the male POA,
but in female rats NE turnover decreased approximately 60%. Alteration
s in the frontal cortex of morphine-exposed male and female rats resem
bled the pattern in the hypothalamus; however, the differences did not
reach statistical significance. In addition, prenatal morphine had no
effect on striatal or cerebellar NE or on basal levels or turnover of
DA in any brain regions. These results demonstrate that prenatal morp
hine alters the content and turnover of NE in a sexually dimorphic man
ner in specific brain regions of male and female rats, suggesting alte
rations in the density of terminals and/or utilization of NE. These se
xually dimorphic alterations in hypothalamic NE induced by prenatal mo
rphine may be related to the changes observed in adult male and female
sexual behavior in our previous work.