THE EXPRESSION OF FOS IN THE WHOLE BRAIN OF RATS FOLLOWING COMPLEX DOUBLE ROTATION ON TWO AXES / 神经解剖学杂志

ABSTRACT

To investigate the relationship of the rotation stimulation with motion sickness, the expression of Fos protein in the whole brain of the rat stimulated by complex double rotation on two axes was observed in the present study. The rats were randomly divided into four groups normal contral group; double-axes rotation stimulation group; the bilateral labyrinthectomy group; group of two-axes rotation stimulation after the bilateral labyrinthectomy. Immunohistochemical staining method was used to detect the expression of Fos protein in different regions of whole brain of the rat. The present results showed that (1) No Fos-like immunoreactivity was detected in the brain of the rats in control group and the bilateral labyrinthectomy group; (2) In the double-axes rotation stimulation group, the Fos-like immunoreactive neurons were observed in many regions of the brain and brainstem of the rats following complex double-axes rotation stimulation, and the Fos-immunoreactivities were expressed in the nucleus. These Fos-immunopositive neurons were intensively distributed in different subnuclei of the vestibular nucleus complex (including medial, superior and spinal nuclei), nucleus of the solitary tract, locus coeruleus, medial and lateral parabrachial nucleus of the brainstem, paraventricular nucleus of the diencephalons and the amygdala of the limbic system; (3) The expression of Fos protein can be scarcely detected around forementioned regions in brains of the rats following complex two-axes rotation stimulation after the bilateral labyrinthectomy. The present results suggest that the double-axes rotation stimulation can activate effectively the vestibular neurons and many neurons of other region of the brain and brainstem are further activated through direct or indirect connections with vestibular nuclei after complex double rotation stimulation. These activated neurons may be related to the complex mechanism of the motion sickness.