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Single Cell Measurement of Dopamine Release with Simultaneous Voltage-clamp and Amperometry
Published on: November 21, 2012
Endogenous hyperprolactinaemia enhances amphetamine- and apomorphine-induced stereotypy
European Journal of Pharmacology
|June 19, 1981
Summary
Rats with high prolactin levels showed increased sensitivity to amphetamine and apomorphine, specifically in drug-induced stereotypy. This suggests selective dopamine receptor supersensitivity in these animals.
Area of Science:
- Neuropharmacology
- Endocrinology
Background:
- Endogenous hyperprolactinemia can alter brain function.
- Dopaminergic pathways are implicated in behavioral responses to psychostimulants.
Purpose of the Study:
- To investigate the effects of endogenous hyperprolactinemia on behavioral responses to dopaminergic drugs.
- To explore potential alterations in dopamine receptor sensitivity.
Main Methods:
- Induction of endogenous hyperprolactinemia in rats via pituitary homografts.
- Administration of amphetamine and apomorphine.
- Assessment of stereotyped behavior, locomotor activity, rearing, and grooming.
Main Results:
- Rats with hyperprolactinemia exhibited enhanced stereotyped behaviors in response to amphetamine and apomorphine.
- No significant changes were observed in locomotor activity, rearing, or grooming.
Conclusions:
- Endogenous hyperprolactinemia selectively enhances sensitivity to certain dopaminergic drugs.
- Suggests the development of postsynaptic dopaminergic receptor supersensitivity, likely within the nigro-striatal system.
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