The effects of neonatal exposure to alcohol and/or cocaine on two measures of stress were studied in juvenile and young adult female rats. After implantation with an intragastric cannula, subjects were artificially reared from postnatal days 4-10. This "brain growth spurt" period is roughly equivalent to CNS development during the third trimester of human pregnancy. There were five treatment groups: alcohol (6 g/kg/day), cocaine (60 mg/kg/day), alcohol/cocaine (6 g/kg/day alcohol and 60 mg/kg/day cocaine), stock (an artificially reared control), and sham (a suckled control). Subjects were tested in open field and forced swim tests beginning at 21 or 60-70 days of age, respectively. Compared to controls, alcohol-exposed females displayed longer latencies to become immobile in the forced swim test as juveniles and cocaine-exposed females showed increased immobility as adults. Increased immobility can be interpreted as hyporesponsiveness to stress. In contrast, very few differences were observed in the open field. Furthermore, the group exposed to alcohol and cocaine in combination did not differ from controls in either paradigm. These findings suggest that the forced swim test may be more sensitive to neonatal drug effects than open field, although these effects may not be consistent across age.
|Number of pages||9|
|Journal||Neurotoxicology and Teratology|
|State||Published - Jan 2005|
Bibliographical noteFunding Information:
This work was supported, in part, by NIH AA09723 to SB and by a dissertation fellowship award from the University of Kentucky to LHT. The authors would like to thank Dr. Jim Herman for consultation regarding stress testing in rats. The authors would also like to thank Bryan Baseheart for technical assistance with this project.
ASJC Scopus subject areas
- Developmental Neuroscience
- Cellular and Molecular Neuroscience