Experimental study of the whole body response in rabbits by linear acceleration and/or optokinetic stimulation

点击翻译按钮获取中文摘要

To study neural mechanisms of motion sickness in rabbits, we examined the physiological and biochemical body responses by several kinds of vestibule-visual conflict (VVC) stimulation (Type 1, Type 2a, Type 2b) for 300sec. Vestibular stimulation (VES) was linear oscillatory acceleration (amplitude:50cm, frequency:0.29Hz or 0.14Hz, direction: X=longitudinal, Y=transverse, Z=vertical) and visual stimulation (VIS) was optokinetic stimulation (random dot pattern drum with uniform velocity). Type 1 VVC stimulation was VES with VIS, Type 2a was VES without visual input and Type 2b was VIS only. Main results were as follows; 1. Heart rates (HR) decreased and coefficient of variation of R-R interval (CV-RR) increased during longitudinal Type 2a. And after atropine injection or bilateral labyrinthectomy, the changes of HR and CV-RR vanished. 2. Whole body responses during Type 2b were smaller than during Type 2a. 3. On body responses during Type 1, there was much difference between each rabbit. These results suggested that the extent of body responses differred by type of VVC stimulation, and in particular linear acceleration affected vestibule-autonomic reflex probably otolith-parasympathetic nerve reflex. Our results that the change of body responses decreased if VVC stimulation dissolved supported sensory conflict theory.