Abstract
Background: Prenatal tobacco smoke exposure is associated with alterations in motivated behavior in offspring, such as increased consumption of highly palatable foods and abused drugs. Animal models show that gestational nicotine (GN) exposure mediates changes in responding for sucrose and drug reward. Methods: A novel, intermittent low-dose intravenous (IV) exposure model was used to administer nicotine (0.05. mg/kg/injection) or saline 3 ×. /day to rats on gestational days 8-21. Two experiments investigated the effect of IV GN on (1) the habituation of spontaneous locomotor activity and on (2) sucrose reinforced responding in offspring. For the operant experiments, animals acquired fixed-ratio (FR-3) responding for sucrose, 26% (w/v), and were tested on varying concentrations (0, 3, 10, 30, and 56%; Latin-square) according to a FR-3, and then a progressive-ratio (PR) schedule. Male and female adult offspring were used. Results: IV GN did not alter birth or growth weight, or the number of pups born. No between-group differences in habituation to spontaneous locomotor activity were observed. FR testing produced an inverted U-shaped response curve, and rats showed peak responding for 10% sucrose reinforcement. Neither gestation nor sex affected responding, suggesting equivalent sensitivity to varying sucrose concentrations. PR testing revealed that GN rats showed greater motivation for sucrose reinforcement relative to controls. Conclusions: A low-dose, IV GN exposure model resulted in increased motivation to respond for sucrose reinforcement in adult offspring. This suggests that using a low number of cigarettes throughout pregnancy will result in increased motivation for highly palatable foods in adult, and perhaps, adolescent offspring.
Original language | English (US) |
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Pages (from-to) | 299-306 |
Number of pages | 8 |
Journal | Drug and Alcohol Dependence |
Volume | 124 |
Issue number | 3 |
DOIs | |
State | Published - Aug 1 2012 |
Funding
Funding for this study was provided by the National Institute on Drug Abuse , DA021287 , and the University of South Carolina Research Productivity Scholar grant, KA-21 . Neither the National Institute on Drug Abuse nor the University of South Carolina had a further role in the preparation of the experimental procedures, the writing or the submission of the manuscript.
Keywords
- Gestational nicotine
- Locomotor activity
- Rats
- Sex
- Sucrose-maintained responding
ASJC Scopus subject areas
- Psychiatry and Mental health
- Pharmacology (medical)
- Toxicology
- Pharmacology