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Opiate regulation of behavioral selection during lactation
Marcia H Sukikara1, Maira D Platero, Newton S Canteras
1Departamento de Patologia, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Orlando Marques de Paiva, 87, "Cidade Universitária" 05508-900, São Paulo, SP, Brazil.
Pharmacology, Biochemistry, and Behavior
|July 13, 2007
Summary
Opioid systems influence maternal care versus hunting behavior in lactating rats. Morphine decreased maternal care and increased hunting, while naloxone reversed these effects, suggesting endogenous opioids may promote hunting.
Area of Science:
- Neuroscience
- Behavioral Biology
- Animal Behavior
Background:
- Opioid system modulation affects maternal behavior and foraging in adult animals.
- Lactating rats present a unique model for studying behavioral trade-offs.
Purpose of the Study:
- To investigate the role of opioid systems in the behavioral choice between maternal care and insect hunting in lactating rats.
- To determine how morphine and naloxone influence this behavioral selection.
Main Methods:
- Acute administration of morphine (3.0 mg/kg) to lactating rats.
- Administration of the opioid antagonist naloxone to morphine-treated and control lactating rats.
- Quantification of maternal behavior (pup care) and predatory behavior (insect hunting efficiency).
Main Results:
- Morphine treatment significantly decreased maternal behavior and increased insect hunting efficiency.
- Naloxone administration reversed the effects of morphine, restoring maternal care and reducing hunting.
- Naloxone alone decreased insect capture and increased maternal nursing behavior.
Conclusions:
- Opioid systems play a crucial role in regulating the balance between maternal care and hunting behavior during lactation.
- Endogenous opioids may stimulate hunting behavior, potentially by suppressing maternal care.
- These findings offer insights into the neurobiological mechanisms underlying behavioral selection in lactating mammals.
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