Appearance of EMG activity and motor asymmetry after unilateral lesions of the dopaminergic innervation to the subthalamic nucleus in the rat.
The effects of unilateral injections of 6-hydroxydopamine into the subthalamic nucleus on muscular rigidity and on motor behavior were examined. Muscular rigidity was judged by the appearance of electromyographical activity in the gastrocnemius-soleus muscle and motor behavior by the turning induced by DL-methamphetamine. The unilateral injection of 6-hydroxydopamine produced the appearance of electromyographical activity ipsilateral to the injected side and ipsilateral turning in response to systemic administration of DL-methamphetamine. These results suggest that the dopaminergic innervation exerts a tonic inhibitory action on the spontaneous activity of the subthalamic neurons. The loss of this action would cause muscular rigidity and motor asymmetry.
Flores
G
G
Departamento de Fisiologia, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico D.F., México.
Valencia
J
J
Rosales
M G
MG
Sierra
A
A
Aceves
J
J
D000818:Animals; D001640:Bicuculline / Q000494:pharmacology; D004298:Dopamine / Q000502:physiology*; D004576:Electromyography / Q000187:drug effects; D008297:Male; D008694:Methamphetamine / Q000494:pharmacology; D009043:Motor Activity / Q000502:physiology*; D009127:Muscle Rigidity / Q000139:chemically induced; D016627:Oxidopamine / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D013239:Stereotyped Behavior / Q000187:drug effects; D009435:Synaptic Transmission / Q000187:drug effects; D013787:Thalamic Nuclei / Q000502:physiology*; D005680:gamma-Aminobutyric Acid / Q000502:physiology
D008694:Methamphetamine; D005680:gamma-Aminobutyric Acid; D016627:Oxidopamine; D004298:Dopamine; D001640:Bicuculline