Abstract
The importance of the infants cholecystokinin (CCK) system for eliciting optimal maternal care was examined in 6 9-day-old Sprague Dawley rats. After administration of either vehicle. CCK-8 (1 or 8 μg/kg) or devazepide (1 mg/kg: a selective CCK(A) receptor antagonist), pups were either individually isolated (Experiment 1) or individually reunited with their dam (Experiment 2) and the rats behavior was observed. When isolated, pups that received devazepide displayed significantly more head-lifting anti wall-climbing attempts than vehicle-treated controls, suggesting that endogenous CCK dampens activity. Devazepide-treated rats were found more frequently in proximity with their mothers when reunited with them, and they emitted more ultrasonic vocalizations compared to vehicle controls. Pups treated with 1 μg/kg CCK received less body licking than vehicle controls. In addition dams hovered and crouched over devazepide-treated pups more than over pups treated with 1 μg/kg CCK. The results suggest that endogenous CCK his a calming quieting effect in the neonatal pup and that this, in turn, results in less infant-mother attractivity and reduced levels of maternal care.
Original language | English |
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Pages (from-to) | 843-851 |
Number of pages | 9 |
Journal | Pharmacology Biochemistry and Behavior |
Volume | 59 |
Issue number | 4 |
DOIs | |
State | Published - Apr 1998 |
Bibliographical note
Funding Information:The authors thank Dr. Elliott M. Blass for comments on a previous draft of the article, Iris Herman Gispan for performing Experiment 3, Aviram Rozin for his advice, and Ofra Schwartz for technical assistance. The authors are very grateful to Merck Co., West Point, PA, for the generous gift of devazepide. A portion of this research was part of an M.A. thesis in Psychology (L. D). Another portion of this research was supported by a grant from the Israel Science Foundation (A. W.)
Keywords
- Cholecystokinin (CCK)
- Devazepide
- Infant-mother interactions
- Maternal behaviour
- Neonatal rats
- Ultrasonic vocalization