Correlation between electrical activity of type I neuron and c-Fos expression in the medial vestibular nuclei following unilateral labyrinthectomy in rats .
- Author:
Byung Rim PARK
1
;
Nam Yong DOH
;
Min Sun KIM
;
Sang Woo CHUN
;
Moon Young LEE
;
Sung Ho LEE
Author Information
1. Department of Physiology, Wonkwang University School of Medicine, Iksan 570-749, South Korea.
- Publication Type:Original Article
- Keywords:
Unilateral labyrinthectomy;
Medial vestibular nuclei;
Vestibular compensation;
Eye movement;
Electrical activity;
c-Fos
- MeSH:
Animals;
Compensation and Redress;
Eye Movements;
Neurons*;
Rats*;
Vestibular Nuclei*
- From:The Korean Journal of Physiology and Pharmacology
1997;1(5):505-513
- CountryRepublic of Korea
- Language:English
-
Abstract:
To search the correlations between electrical activity and c-Fos expression in the process of vestibular compensation, we examined the changes of those two parameters in the medial vestibular nuclei (MVN) of unilaterally labyrinthectomized (ULX) rats. Spontaneous nystagmus with fast component toward the intact side disappeared gradually within 48 hours. Fourty eight hours after ULX, directional preponderance of the eye movement induced by sinusoidal rotation of the whole body which represents the symmetry of bilateral vestibular functions showed less than 20% by rotation of 0.1, 0.2, and 0.5 Hz, indicating the recovery of symmetry in bilateral vestibular functions. Six hours after ULX, spontaneous electrical activity of type I neurons resulted in asymmetry between bilateral MVN, however, the asymmetry of the electrical activity was decreased 48 hours after ULX. Immunocytochemical staining revealed that ULX produced dramatic induction of c-Fos positive cells in the MVN bilaterally. The number of c-Fos immunoreactive cells in the contralateral MVN was significantly higher than those in the ipsilateral MVN (p<0.0001) 2 hours after ULX. Thereafter, the number of c-Fos positive cells decreased bilaterally and was slightly, but not significantly higher in the ipsilateral MVN at 48 hours after ULX. The present results suggest that both electrical activity of type I neurons and c-Fos expression in MVN following ULX will reflect underlying mechanisms of recovery process of vestibular compensation.
