Nystagmic responses of hippocampal origin with reference to excitability of cholinergic and adrenergic components involved in the hippocampus of rabbits
Hinoki, M.; Nakanishi, K.; Ito, S.
Agressologie 20(1): 11-18
1979
ISSN/ISBN: 0002-1148 PMID: 507315 Document Number: 140002
Nystagmic responses of hippocampal origin are divided into 2 types; i.e., prompt and delayed. The former type of nystagmic response is elicited soon after injection of carbachol into the hippocampus of a normal rabbit. It is a horizontal nystagmic response directed to the side of the injection and is accompanied by an arousal state in the EEG. In the case of nystagmic response of the prompt type, there is no preceding suppressive phase of the EEG. The latter type of nystagmic response is a horizontal nystagmic response directed to the right and the left and appears with a fairly long latency. It is elicited in a normal rabbit on the basis of a rebound in the EEG, brought about by injection of carbachol into the hippocampus. It is also elicited in rabbits with repeated electric stimulations of the hippocampus on the basis of a rebound in the EEG, brought about by injection of adrenaline into the same brain. In the case of nystagmic response of the delayed type, there is a marked preceding suppressive phase of the EEG. Repeated electric stimulation of the hippocampus results in alterations of the activity of the 2 kinds of nervous components described above. After the electric stimulation, 2 types of nystagmic responses can hardly be induced with an injection of carbachol. Nystagmic response of the delayed type is easily induced with an injection of adrenaline.