JAPANESE CIRCULATION JOURNAL

Show abstractHide abstract

The influences of the cervical sympathetic nerve and of the vagal nerve were experimentally studied using dogs and rabbits. In dogs, the operation procedure to seperate the intracranial and the extracranial circulat.ion was devised. Stimulation of the cervical sympathetic nerve decreased the blood flow in the external carotid arteries both in dogs and in rabbits more intensely than in the internal carotid arteries, showing more weak sympthetic constrictive control of the cerebral blood vessels than that of the extracranial blood vessels. In the depressor responses elicited by the stimulation of the cervical vagal nerve, the blood fllow in the internal carotid arteries followed the change in the systemic blood pressure. The reduction of the blood pressure was more marked after cervical sympathectomy than before cervical sympathectomy and it was concluded that the sympathetic vasodilatatory control might not be operating in the depressor responses, distinctly contrasted with the case in the external carotid arteries. In the external carotid arteries, the operation of the vasodilatatory factor during the depressor responses was demonstrated. Mechanisms that caused vasodilatation of the cerebral blood vessels during the depressor responses by the vagal stimulation were discussed.

View full abstract

Download PDF (2160K)

Register with J-STAGE for free!