A neuropharmacological and electrophysiological study was carried out in order to investigate the mechanism of the sciatic and trigeminal evoked eyelid microvibration (SMV and TMV), and blink reflex (BR) in rabbits.
The results obtained wer e as follows;
1. The response of SMV, induced in the upper eyelid by sciatic nerve stimulation, was composed of three components, which had peak latencies of 44±10,63±11, and 84±7msec, respectively.
2. The pe ak latency of the nociceptive reflex (SNR), recorded simultaneously in the anterior tibial muscle, was 13±5 msec.
3. The latency time of SMV and S NR was not changed statistically by the repeated electric stimulation of the sciatic nerve, but the amplitude indicated habituation.
4. There was no difference in the latency time of SMV, induced in the left upper eyelid, between the response to the sciatic stimulation of the left site and that of right site.
5. Each SMV component was increased in amplitude by the low dose of barbiturate and decreased by the high dose. It was also suppressed, dose-dependently, by TRH. CD P choline suppressed the SMV1 and SMV₂ components, but increased that of SMV₃. Cardiazol increased SMV component in a low dose, but decreased it in a h i gh dose. The SMV was little influenced by amphetamine.
6. The amplitude of SNR increased w i th barbiturate and CDP-choline, but decreased with TRH, cardiazol and amphetamine.
7. SMV and SNR respon ded to most of the agents in the same way, but an antagonistic relationship was observed, in part, in the response between SMV and SNR.
8. Three components were also recorded in the TMV, their peak latencic s being 32±10,53±11 and 71±12 msec, respectively.
9. The BR recorded simultaneously consisted of two components; the peak latencies of which were 3 and 10±1 msec, respectively.
10. Barbiturate, TRH, cardiaz o l and morphine, administered intravenously, suppressed each TMV component, and the effect of morphine was the strongest. CDP-choline increa s e d each TMV component.
11. BR was sup pressed in amplitude by all agents.
12. The TMV and BR responses to these ag ents showed almost the same behavior.
13. A lesion in the sensory relay nucleus, such as posterolateral ventral nucleus (VPL)and posteromedial ventral nucleus (VPM), increased each TMV component, w h i le it decreased that of BR.
14. Impairments of the nucleus reticularis (RET), the nucleus centrum medianum (CM), the nucleus ventralis medialis pars lateralis (VML) and the nucleus lateralis posterior (LP ), which belong to the non-specific projection nuclei, also decreased each TMV component, and increased that of BR. There was no definite trend with TMV and B R respone when the nucleus ventralis anterior (VA) and the nucleus ventralis lateralis (VL ) were impaired.
15. The amplitude of each TMV component decreased with a lesion in the brain stem reticular formation (RF), while that of BR increased.
16. Lesion in the oculomotor nuclei (III-nucl. ) su ppressed each TMV component completely, but that of BR, moderately.
17. Impairment of the subthaIamus (STH) decreased the amplitude of the first component of TMV and that of BR.
18. Impairment of the cap sula interna (IC) and optic tract (OT) did not show any definite response in TMV and BR.
These results indicate that the TMV response appears to be the same as that of SMV in mediating, in part, the same relay nucleus or synapse of the central nervous system, and that it differs from BR in the mechanism of response.

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An electrophysiological study was made on kindled rabbits, which were prepared in the amygdaloid nucleus, hippocampus, cerebral cortex and so on, on the threshold of the arousallike reaction and the evoked muscular discharge due to stimulation of the cerebral cortex and separatedly the stimulation of hippocampus on another kindled rabbits.
The gastric lesion was also examined.
1) In control group, one w ith no changes and others with some rises were observed in the threshold of arousal-like reaction and evoked muscular discharge due to 100 Hz stimulation of cerebral cortex.
2) In amygdaloid kindled group, both the threshold of the arousal-like reaction and the evoked muscular discharge due to 100 Hz stimulation of cerebral cortex declined.
3) In hippocampal kindled group, both the thresholds by 100 Hz s timulation of cerebral cortex also decreased.
4) In co rtical kindled group, both the thresholds by 100 Hz stimulation of cerebral cortex decreased like in other two kindled groups.
5) In control group, certain rise on every rabbit was observed in the threshold of evoked muscular discharge due to 100 Hz stimulation of hippocampus.
6) In amygdaloid kindled group, the threshold of evoked muscular discharge due to 100 Hz stimulation of hippocampus declined.
7) In control group, gast ric erosion cases showed at the rate of 20%.
8) In kindled groups, overall gastric erosion cases appeared at the rate of 68%. Namely its rate was 80% in amygdaloid kindled group and 100% in hippocampal kindled one. On the other hand, in cortical kindled one its rate was low, which was 42%.
9) Stomach ulcer was found in two cases, and one was in am ygdaloid kindled rabbit and the other was in septal kindled one.
Based on the above results, it can be concluded that kindling phenomena of neocortex, paleocortex and archicortex all have facilitating effects on the level of consciousness and motor activity.
And the gastric findings indicate that the kindling phenomena can be applied to an experimental model of a stress disease.

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The changes in consciousness and motor activity due to exteroceptive stimulation in the presence and the absence of flash stimuli were studied in the kindled rabbits. The exteroceptive stimulation consisted of the attachment of a har d contact lens (CL) to the eye of the rabbits.
1) In control group, the threshold of the arousal-like reaction and the evoked muscular discharge due to 100 Hz stimulation of the cerebral cortex increased on attachment of CL in the absence of flash stimuli, but decreased in the presence of flash stimuli.
2) In amygdaloid kindled group and hippocampal kindled one, the threshold of the arousallike reaction and the evoked muscular discharge due to 100 Hz stimulation of the cerebral cortex decreased on attachment of CL both in the presence and the absence of flash stimuli.
These findings in kindled rabbits suggest that exteroceptive stimulation facilitates farther excitability of the brainstem reticular formation and the level of consciousness and motor activity.

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With amygdaloid kindled rabbits, effects of DN-1417 (TRH analog) were examined on electrical phenomena; (a) the thresholds of the arousal-like reaction and of the evoked muscular discharge due to 100 Hz stimulatiou of the cerebral cortex, and (b) the afterdischarge duration.
For the purpose of comparison, the effect of Pentobarbital was examined on another group of amygdaloid kindled rabbits.
DN-1417 was intraven ously administerd at three different doses (0.2,2.0 and 20.0mg/kg)Pentobarbital was intravenously administerd at three different doses (0.5,3.0 and 5.0mg/kg).
1) DN-1417 elevated the thresholds of the arousal-like reaction and of the evoked muscular discharge at the dose of 2.0mg/kg i. v. and lasted for 10 to 30 min. But DN-1417 had no effect at other doses.
2) Pentobarbital elevated the thresholds of the arousal-like reaction and of the evoked muscular discharge. This drug had a dose-dependent effect.
3) DN-1417 induced afterdischarge to disappear o r reduce at the dose of 2.0mg/kg i. v. for 10 to 30 min. But this dr ug had no effect at other doses.
4) Pentobarbital induced afterdischarge to disappear or reduce. The effect was dose-dependent. These findings s how that DN-1417 has a dose-independent anticonvulsant effect while Barbiturate has a dose-dependent effect.

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Flow cytometry (FCM) has been used widely for clinical diagnosis and evaluation of chemotherapy. The author has conducted monolayer-culture of brain tumor cells and reported the changes of DNA-histograms of brain tumor cells for antineoplastic agents. In this paper, a new application of FCM was established to evaluate the choice of the best antineoplastic agent in chemotherapy for malignat brain tumor.
After adjusting cell preparation and eva luating the analytic system of FCM, the sensitivity test to antineoplastic agents was developed through preliminary studies using the established brain tumor cell line. Antineoplastic agents were challenged to the cells in monolayer-culture, and the changes of DNA-histograms as well as cell viability were analyzed by FCM. Cell viability was measured by the FDA (Fluorescein Diacetate) vital staining method, and propidium iodide was used for the analysis of DNA-histograms. Judgment of the best agent was conducted, based on its effects on the changes of their cell kinetics.
Cytocydal and cytostatic effects were evaluated quantita tively, and the results showed a well coincidence with the sensitivity of the cells to the appropriate antineoplastic agent.
Secondly, the above system was applied to the clinical cases of 15 malignant b rain tumors. The best antineoplastic agent was selected for each case through this method and good therapeutic effects were demonstrated. The present results suggest that the above method is of much clinical value.

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Auditory brain stem response (ABR), which has been recently used as an objective method for evaluation of the brain stem function, plays an important role in the neurosurgical field. However, there are only a few reports on ABR of the posterior fossa mass lesion. The analytical study of ABR in 20 cases of the posterior fossa mass lesion is reported. The most frequent changes of ABR in infratentorial space occupying lesions are the delay of the latency of Wave III, and the elongation of the interpeak latency between Wave III and V, and Wave IV and V. In the localized lesion, they show the prolonged latency of Wave I in the affected side. These results suggest that the most prominent and early effects in the infratentorial space occupying lesions appear in the upper pons and the mid brain.

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