Summary
EMG potentials were recorded simultaneously with spontaneous intracellular multifocus slow potentials in the rabbit superior rectus under general anesthesia. Those EMG potentials which were synchronous with such intracellular potentials, are essentially monophasic and at least 4 msec in duration, clearly different from spike potentials. It was verified, that the fibers which produce such spontaneous intracellular multifocus slow potentials are indeed multiply innervated. The study of such slow potential activity in human extraocular muscles may be profitable.
Résumé
Sur le muscle droit supérieur du lapin anesthésié on a enregistré simultanément des potentiels EMG et des potentiels intracellulaires lents prenant naissance dans des foyers cellulaires multiples. Quelques enregistrements ont montré l'apparition synchrone de potentiels EMG et de potentiels intracellulaires lents ‘multi-foyers’; dans tous ces cas les potentiels EMG étaient essentiellement monophasiques et d'une durée supérieure à 4 msec, présentant ainsi des caractéristiques différentes de celles d'un potentiel de pointe propagé. Il a pu être vérifié que les fibres musculaires qui donnent naissance aux potentiels intracellulaires lents multifoyers, sont des fibres à innervation multiple. L'étude des potentiels lents chez l'homme pourrait être intéressante.
Zusammenfassung
Im Rectus superior des Kaninchens wurden in Narkose gleichzeitig EMG Potentiale und spontane langsame, intracelluläre multifokale Potentiale registriert. Die EMG Potentiale, die mit den intracellulären Potentialen synchron auftreten, sind hauptsächlich monophasisch, sie dauern wenigstens 4 msec und unterscheiden sich deutlich von den ‘Spike’-Potentialen. Es hat sich bestätigt, daß die Fasern, welche solche spontanen, intracellulären, multifokalen langsamen Potentiale hervorrufen, tatsächlich eine mehrfache Innervation besitzen. Es wäre interessant, auch beim Menschen diese langsamen Potentiale zu untersuchen.
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Supported by research grant NB 00911-12A1 From N. I. H. and by postdoctoral research fellowship awards from the National Council to Combat Blindness, Inc. No. TF-173 (C4) to Tetsuma Ozawa and No. F 180 to Kensei Cheng.
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Ozawa, T., Cheng-Minoda, K., Davidowitz, J. et al. Correlation of potential and fiber type in extraocular muscle. Doc Ophthalmol 26, 192–201 (1969). https://doi.org/10.1007/BF00943976
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DOI: https://doi.org/10.1007/BF00943976