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PubMed · 8873138

Muscarinic antagonists microinjected into the subthalamic nucleus decrease muscular rigidity in reserpinized rats.

S Hernández-López·G Flores·M G Rosales·A Sierra·D Martínez-Fong·J Aceves
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Abstract

The ability of anticholinergic agents microinjected into the subthalamic nucleus to reduce reserpine-induced muscular rigidity was assessed in rats. The electromyographical activity of the gastrocnemius-soleus muscle was used as a parameter of muscular rigidity. Reserpine (5 mg/kg i.p.) produced the appearance of electromyographical activity. The muscarinic antagonists M3 (1.27 nmol of 4-DAMP) and M1 (2.36 nmol of pirenzepine) markedly reduced the reserpine-induced electromyographical activity, whereas the M2 antagonist AFDX-116 (2.37 nmol) had no effect. These results suggest that a high cholinergic tone in the subthalamic nucleus is associated with the reserpine-induced muscular rigidity. Moreover, the M3 muscarinic antagonist is more effective than the M1 muscarinic antagonist in reducing the muscular rigidity in reserpinized rats, a model of Parkinson's disease, by blocking the high cholinergic tone in the subthalamic nucleus.

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Anesthetics, IntravenousAnimalsChloral HydrateCholinergic AntagonistsElectromyographyLocomotionMaleMicroinjectionsMuscarinic AntagonistsMuscle RigidityMuscle, SkeletalPiperidinesPirenzepineRatsRats, WistarReserpineSympatholyticsThalamic NucleiJournal ArticleResearch Support, Non-U.S. Gov't

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S Hernández-López, G Flores, M G Rosales, A Sierra, D Martínez-Fong, J Aceves. 1996-08-09. Muscarinic antagonists microinjected into the subthalamic nucleus decrease muscular rigidity in reserpinized rats.. https://pubmed.ncbi.nlm.nih.gov/8873138/

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