The Effect Of The Damage Stimulation Of The Vestibular Organ On Sympathetic Nerve And Vagal Verve In The Neck

Motion sickness, a disease induced by abnormal motion, shows a misregulation of autonomic nervous system, including sweating, salivating, indifference, enjoying sleeping, belly discomfort, faintness and sick. Semicircular canal and otolith in vestibular system are receptors of circumrotating and lineal shifting gears movement. Their functions include feeling the location and movement of head, maintaining balance of body and inner-environment, mediating eye movement and breath. At present, motion sickness induced by riding, embarking and emplaning is considered as a result of unconventional activity of vestibular system. So, the study is hot in how vestibular system mediates splanchnic activity. The solution of this problem is important for prevention and cure of motion sickness.Abnormal signal introduction to vestibular system is one of the main reasons for motion sickness with a distinct character of nausea. According to this phenomena, signals from vestibular system must reach intestines and stomach overpass vagal nerve. However, it is still not well known about the connection of the signal introduction from semicircular canal and otolith with the signal out from autonomic nervous. In order to solve this problem, a hypothesis has been supposed: the utricles exert a predominantly sympatho-excitatory influence via their interactions with brain noradrenergic pathways, while the semicircular canals increase parasympathetic tone via their cholinergic brain stem and cerebellar projections. But there is no enough evidence to support this hypothesis, the nature of this connection remains in dispute.20 pigeons was used in this study, we stimulated the vestibular system and then recorded the discharge of the sympathetic nerve and parasympathetic nerve. We studied the following questions: (1) Damage stimulates the otolith of 10 pigeons, and we recorded the electric discharge changes of sympathetic nerve and parasympathetic nerve. (2) Damage stimulates the lateralis semicircular canal of 10 pigeons, and we recorded the electric discharge changes of sympathetic nerve and parasympathetic nerve. The results are as follows:1.The changes of sympathetic nerve and parasympathetic nerve appear after damage stimulates the otolith.9 pigeons have a significant increase in electric discharge changes of sympathetic nerve (p<0.01), but 1 does not (p>0.05). Statistical analysis shows that the otolith stimulation can activate sympathetic nerve. At the same time, vagal nerve electric discharges show the following result: 7 pigeons have a significant decrease in electric discharge changes of parasympathetic nerve (p<0.01), but 1 has significant increase (p<0.01), and 2 have no differences (p>0.05). Statistical analysis also shows that otolith stimulation have no effect on vagal nerve.2. The changes of sympathetic nerve and parasympathetic nerve appear after damage stimulates the semicircular canal.6 pigeons have a significant decrease in electric discharge changes of sympathetic nerve (p<0.01), but 3 have significant increase (p<0.01) and 1 have no difference (p>0.05) under control. Statistical analysis shows that otolith stimulation have no effect on sympathetic nerve. At the same time, vagal nerve electric discharges are as follow: 8 pigeons have a significant decrease in electric discharge changes of vagal nerve (p<0.01), but 2 have no difference (p>0.05) under control. Statistical analysis displays that semicircular canal stimulation can inhibit vagal nerve activity.The results above indicated: (1)The tolith can activate sympathetic nerve, but the effect on vagal nerve is uncertain. (2)The semicircular canal can activate vagal nerve, but the effect on sympathetic nerve is uncertain. The results provided the basal data for elucidating the mechanism of the vestibule-viscus modulation and motion sickness.