Meclofenoxate hydrochlorideの中枢作用機序に関する電気生理学的研究

ELECTROPHYSIOLOGICAL STUDIES OF THE EFFECTS OF MECLOFENOXATE HYDROCHLORIDE ON THE CENTRAL NERVOUS SYSTEM

I．緒言

　Meclofenoxate hydrochlorideはわが国においてもすでに実際臨床において意識障害あるいはめまいなどの治療薬として広く使用されている薬物である。そしてその作用機序についても電気生理学的^1），電子顕微鏡的研究^2）が行なわれており，脳循環に及ぼす影響についても検討されている^3）。しかしその詳細な中枢作用機序についてはまだ充分に明らかにされたとはいいがたい。本研究はそのようなまだ充分に明らかにされていないMeclofe—noxate hydrochlorideの中枢作用機序を電気生理学的な面より明らかにするために行なったものである。

An electrophysiological study was made of effects of meclofenoxate hydrochloride on the central nervous system of rabbits.

1. Meclofenoxate hydrochloride lowered the threshold of arousal reaction following stimulation on the brainstem reticular formation, but showed no reaction to the muscular discharge simultane-ously evoked in the fore and hind limbs.

2. Meclofenoxate hydrochloride showed a facil-itatory effect on the muscular discharge in the fore and hind limbs following stimulation of the cere-bral cortex, and either a facilitatory or inhibitory effect on muscular discharge due to stimulation of the hippocampus.

3. Regarding the afferent average evoked poten-tial of the cerbral cortex due to stimulation of the sciatic nerve, meclofenoxate hydrochloride showed a facilitatory effect on N₁, N₂, N₃ and P components and both facilitatory and inhibitory effect on N₄ and N₅ components.

4. Meclofenoxate hydrochloride showed a facil-itatory effect on nociceptive reflex discharge, an inhibitory effect on H wave, and only a little effect on M wave.

5. Meclofenoxate hydrochloride showed a facil-itatory effect on unit discharge in the brain stem reticular formation.

It was demonstrated that meclofenoxate hydro-chloride showed an arousal effect on consciousness and a facilitatory effect on the afferent pathway and on the pyramidal pathway and an excitatory action on some nerve cells in the central nervoussystem.