The Changes Of Mglur4 And Mglur7 In The Medial Vestibular Nucleus And Flocculus Following Unilateral Labyrinthectomy In The Rat

PartⅠThe changes of mGluR4, mGluR7 in the medial vestibular nucleus following unilateral labyrinthectomy in the ratObjective To observe the expression of mGluR4, mGluR7 in the medial vestibular nucleus(MVN) following unilateral labyrinthectomy(UL). Methods 32 SD rats were randomly divided into two groups. 24 animals received unilateral labyrinthectomy while the others maintained labyrinthine well. The immunohistochemistry and western blot were used to observed the change of mGluR4, mGluR7 post-unilateral labyrinthectomy. Results mGluR4 was no expression in the MVN. mGluR7 was decreased in lesioned side MVN after unilateral labyrinthectomy. The 1d post-UL was lowest. Then it was increase , while 3d ,7d and 1m post-UL were same as control group. There are no change between contralateral and control group. Conclusion decrease of mGluR7 contributed to the rebalancing of spontaneous resting activity between the ipsilateral and contralateral MVNs. It is suggested that such changes in the activities of the MVNs may be important to the vestibular compensation process. PartⅡThe changes of mGluR4, mGluR7 in the cerebellar flocculus following unilateral labyrinthectomy in the ratObjective To observe the expression of mGluR4, mGluR7 in the cerebellar flocculus following unilateral labyrinthectomy(UL).Methods 32 SD rats were randomly divided into two groups. animals received unilateral labyrinthectomy while the others maintained labyrinthine well. The immunohistochemistry and western blot were used to observed the change of mGluR4, mGluR7 post-unilateral labyrinthectomy.Results mGluR4 and mGluR7 was decreased in lesioned side flocculus after unilateral labyrinthectomy. The 1d post-UL was low. Then it was increase in 3d post-UL, while 7d and 1m post-UL were same as control group. In the contralateral flocculus, no changes in protein expression were observed.Conclusion the decrease in mGluR4 and mGluR7 in the ipsilateral flocculus may have had the effect or reducing Purkinje cell inhibition of ipsilateral VNC neurons, thereby contributing to the rebalancing of spontaneous resting activity between the ipsilateral and contralateral VNCs. It is suggested that such changes in the activities of the floccular-VNC pathways may be responsible for the vestibular compensation process.