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Dopamine D1 and D2 antagonist effects on response likelihood and duration
Won Yung Choi1, Cecile Morvan, Peter D Balsam
1Columbia University, Department of Psychiatry, New York, New York, USA.
Behavioral Neuroscience
|December 17, 2009
Summary
Dopamine D1 and D2 receptor antagonists differentially affect motor control. D2 receptor blockade prolongs response duration, while D1 receptor blockade reduces response initiation likelihood in behavioral tasks.
Area of Science:
- Neuroscience
- Behavioral Pharmacology
Background:
- Dopamine (DA) transmission deficits are linked to motor abnormalities in Parkinson's disease and experimental models.
- These motor deficits include impaired response initiation and prolonged response execution.
Purpose of the Study:
- To investigate the specific roles of dopamine D1 and D2 receptor subtypes in regulating response initiation and duration.
- To differentiate the effects of D1 and D2 receptor antagonism on Pavlovian and operant behaviors.
Main Methods:
- Administration of D1/D5 antagonist SCH23390 and D2/D3 antagonist raclopride in varying doses.
- Assessment of response likelihood and duration in cued Pavlovian approach and operant lever-press tasks.
Main Results:
- Both D1 and D2 antagonists caused similar locomotor suppression at high doses.
- D2 antagonist raclopride selectively increased response duration in both tasks.
- D1 antagonist SCH23390 selectively decreased response likelihood in both tasks.
Conclusions:
- Dopamine D2 receptors play a preferential role in regulating the duration of behavioral responses.
- Dopamine D1 receptors preferentially modulate the likelihood of initiating behavioral responses.
- These findings offer insights into the distinct roles of dopamine receptor subtypes in motor control.
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