The present study was made in an attempt to clarify the changes in the cephalic circulation and cardiovascular function occurring after stimulation or destruction of the basal ganglia of rabbits in reference to electrical activities of the central nervous system.
The results were as follows.
1. Stimulation of th e globus pallidus with 3Hz resulted in a change in the spike and wavelike pattern in the EEG of the frontal cortex (FC) and hippocampus (HPC). This stimu lation had almost no effect on the blood pressure, heart rate and bilateral common carotid blood flow volume, but there were a few cases with a slight drop in blood pressure and slight decrease in heart rate.
2. Stimulation of the globus pallidus with 8Hz resulted in a change in the recruiting responselike pattern in the EEG of FC and HPC. With this stimulation, there was a drop in blo od pressure, decrease in heart rate and decrease in bilateral common carotid blood flow volume.
3. When the globus pallidus was stimulated with 100Hz, a pattern of desynchr onization became apparent in the EEG of FC and HPC. This stimulation induced a drop in blood pressur e, decrease in heart rate and decrease in bilateral common carotid blood flow volume.
4. The drop in blood pressure and decrease in heart rate induced by stim ulation of the globus pallidus took place even when the bilateral depressor and carotid sinus nerves were sev ered. But, when the vagus nerve was severed bilaterally and atropine sulfate injected intrave nously, the effect decreased.
5. The decrease in bilateral common carotid blood flow volume induced by stimulation of the globus pallidus became even more prominent when the effect of change of blood gases w as eliminated by artificial respiration.
6. Stimulation of th e putamen with 3Hz resulted in a spike and wave-like pattern in the EEG of FC and HPC. When stimulated with 8Hz, a change in the recruiting response-like pa ttern occured and with 100Hz, a pattern of desynchronization was observed in FC and a pattern of synchronization or desynchronization was observed in HPC. Any one of these stimuli had almost no effect on blood pressure and heart rate, but there was an increase in bilateral common carotid blood flow volume.
7. This increase in bilateral common carotid blood flow volume induced by stimulation of the putamen became less when the effect of blood gas variation was eliminated by artificial respiration, and this phenomenon was almost completely suppressed by intravenous injection of atropine sulfate.
8. When the caudate nucleus was stimulated, a change in the EEG was almost same pattern as the change induced by stimulation of the putamen but there was little effect on the blood pressure, heart rate and bilateral common carotid blood flow volume.
9. On destruction of the globus pallidus, putamen, caudate nucleus or internal capsule, slow wave became apparent in the EEG of FC but it was not observed apparently in the EEG of HPC.
10. Blood pressure and heart rate showed little change with any one of these destruction but the common carotid blood flow volume increased with destruction of the globus pallidus and decreased with destruction of the putamen, caudate nucleus or internal capsule.
11. The increase of blood flow volume in bilateral common carotid and bilateral internal carotid arteries, induced by destruction of the globus pallidus, was unaffected even when the influence of blood gas variation was eliminated by artificial respiration, but this trend tended to be lessened by the administration of atropine sulfate.
12. The decrease of blood flow volume i n bilateral common carotid and bilateral internal carotid arteries, induced by destruction of the putamen, was also observed under artificial respiration, but this trend was significantly lessened by the intravenous administration of phenoxybenzamine compared to the untreated control.
View full abstract