Abstract
A neuropharmacological study was made in an attempt to clarify the relationship between the higher central nervous function and cerebral circulation, especially taking notice of muscular discharge, by using the Doppler ultrasonic flowmeter and an electromagnetic flowmeter.
The resu lts obtained were as follows.
1) Blood flow velocity was d etermined to be a fixed quantity through the use of the probe of a Doppler ultrasonic flowmeter which I specially adapted for this experiment.
2) In the case of the arousal reaction and the recruiting response, the effect upon the cerebral blood flow velocity and cerebral blood flow volume increased in the case of the arousal reaction, and decreased or did not change at all in the case of the recruiting response.
3) It wa s made clear that the cerebral blood flow velocity and the cerebral blood flow volume increased not only in the natural spontaneous state, but also in the case of the arousal or the recruiting response during the appearance of muscular discharge.
4) It was determined that the Doppler ultrasonic flowmeter was more sensitive to the cardiovascular dynamics than an electromagnetic flowmeter, when studied from the standpoint of the effects of therapeutic agents on the cerebral blood flow in cases of brain injury.
5) C oncerning the action of therapeutic agents in cases of brain injury, such as ATP, Cytochrome C, CDP-choline and so on, these increases of the cerebral blood flow volume were not observable in so far as no muscular discharge was revealed.
6) Following the administration of phenoxybenzamine and propranolol, it was demonstrated that the increase of the cerebral blood flow volume was related with the a-receptor when the evoked muscular discharge was obtained through the use of an electric stimulation on the midbrain reticular formation.
7) Following the studies of the momentary, instantaneous cerebral blood flow volume accompanied with an electric stimulation of the midbrain reticular formation or nucleus ventralis anterior in the thalamus, the influence of the evoked muscular discharge was most remarkable in the external carotid artery followed secondarily in the vertebral artery, while the tendency of the increased of the cerebral blood flow volume on the internal carotid artery was least detectable.
8) It was noted that the mom entary, instantaneous cerebral blood flow volume by the stimulation of the midbrain reticular formation or nucleus ventralis anterior increased to the maximum within 5 seconds after stimuli and decreased gradually thereafter.
Additional study was made concerning the alteration on the R-R interval of ECG. Also, the systemic blood pressure was examined and the increase of the cerebral blood flow volume indicated by the appearance of muscular discharge was discovered to be related to the increase of 1 cardiac stroke volume.
