Relationship between Hippocampal Theta Rhythm and Pressor Effect during Noxious Stimulus in Rabbits / 第三军医大学学报

ABSTRACT

It is known that hippocampal EEG and blood pressure can be influenced bynoxious stimuli, but the relationship between the hippocampal theta rhythm andthe pressor effect has not been made clear. In this article, the relationship betweennoxious stimulus and the central cholinergic activity after the hippocampal thetarhythm was inhibited or blocked was studied.There was an obvious correlation between the duration of the hippocampal theta rhythm and that of the pressor effect when an noxious stimulus was given. But the duration and reaction of pressor effect were inhibited if 100 ?g of atropine was injected into one of the lateral ventricles and it was strengthened if 100 ?g of mascarine was injected intraventricularly. After the clectrocoagulation of the medial septum, the hippocampal theta rhythm could not be evoked by noxious stimulus and the pressor effect was also obviously inhibited.These results seem to indicate that the hippocampus plays a role in the regulation of blood pressure, the mechanism of which may be mediated through the central cholinergic system.