視床核の機能分化に関する電気生理学的研究DM核とVL核の機能の比較研究

抄録

It is well known that the effective duration of barbiturate's anesthesia is rather to become longer when a certain quantitative combination between barbiturate and cardiazol is applied. Experiments were made to clarify the functional significance of DM and VL in this mechanism. The results were obtained as follows.
1. Such items as arousal reaction, muscular discharge of fore-and-hind limbs, recruiting response and spike-and-wave were evoked by stimulation of DM and VL to discover that the barbiturate acted differently from the cardiazol for the responses induced by DM stimulation and VL stimulation.2.8Hz-DM,8Hz-VL and 100Hz-VL stimulation displayed an inhibitory effect on muscular discharge of fore-and-hind limbs evoked by stimulation of cerebral cortex. The inhibitory effect therof was stronger at 100Hz-VL stimulation.100Hz-DM stimulation induced the facilitatory effect and the inhibitory effect respectively.3. In the experiments of muscular discharge of fore-and-hind limbs evoked by stimulation of hippocampus,8Hz-DM,100Hz-DM and 8Hz-VL stimulation showed the inhibitory effect, but on the contrary, a facilitatory effect was observed at 100Hz-VL stimulation.
4. Both stimulation of DM and VL produced almost no effects either on nociceptive reflex discharge or M wave. However, on H wave,8Hz and 100Hz-DM stimulation showed the inhibitory effect and 8Hz and 100Hz-VL the facilitatory effect.
5. On the afferent average evoked potentials of the cerebral cortex induced by the sciatic nerve stimulation, both DM and VL stimulation, on one hand, showed the facilitatory effect, on such early components as N1 and N2, at which time its effect was stronger when DM was stimulated than when VL was stimulated. On the other hand, on such late components as N4 and N5, DM stimulation showed the facilitatory effect and VL stimulation the inhibitory effect.
6. Both DM and VL stimulation at 8Hz and 100Hz produced the inhibitory effect on the intestinal movement, under which effect 100Hz stimulation acted much stronger than 8Hz stimulation and VL stimulation acted much stronger than DM stimulation.
7. Following the afore-mentioned experiments, a comparative analysis was made to respectively observe the effects of artane, biperiden and CDP-choline on the muscular discharge by VL stimulation and by hippocampus stimulation. This experiment made it clear that diphenylhydantion showed the stronger inhibitory effect on the muscular discharge by VL stimulation than by the hippocampus stimulation. But on the contrary, artane, biperiden and CDP-choline showed the stronger inhibitory effect on the muscular discharge by the hippocampus stimulation than by the VL stimulation.
8. In order to clarify the relationship between the site of stimulation of VL and the inhibitory effect of artane, biperiden and CDP-choline, the flexor and the extensor of the fore-and-hind limbs were indivisually examined. It was thus ascertained that with artane and biperiden, the site of the inhibitory effect was located at the ventromedian site of VL and that with CDP-choline, it was located at the dorsolateral site of VL.
These experimental results well, prove that DM and VL have quite different effects with each other on the extrapyramidal system and that there might be a possibility to determine which drug(s) can effect on Parkinsonism's rigidity and/or tremor by examining the effects of drugs on the muscular discharge by VL stimulation.