Abstract
The role of the entopeduncular nucleus (EP) and the subthalamic nucleus (STN) in mediating dopamine receptor antagonist-induced catalepsy in the rat was investigated. Five days after bilateral lesions of EP and STN respectively with the excitotoxin quinolinic acid (15, 30 nmol/0.5 μl/side and 24 nmol/0.5 μl/side, respectively) rats were injected intraperitoneally with the dopamine D1 receptor antagonist SCH 23390 (0.5 mg/kg) or the dopamine D2 receptor antagonist haloperidol (0.5 mg/kg). Complete EP lesions prevented both SCH 23390- and haloperidol-induced catalepsy. STN lesions exerted pronounced anticataleptic effects in case of haloperidol-induced catalepsy, but less pronounced in case of SCH 233390-induced catalepsy. Further characterization of these anticataleptic effects in an open field demonstrated, that neither EP- nor STN lesions reversed bradykinesia, which occurred after selective dopamine receptor blockade. In conclusion, both EP and STN participate in the mediation of catalepsy induced by dopamine D1- and dopamine D2 receptor antagonists. Thereby these nuclei preferentially mediate rigidity and akinesia, but to a lesser extent bradykinesia.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
