EFFECTS OF COCHLEA REMOVAL ON GABAERGIC TERMINALS IN NUCLEUS MAGNOCELLULARIS OF THE CHICKEN

被引:8
作者
CODE, RA [1 ]
DURHAM, D [1 ]
RUBEL, EW [1 ]
机构
[1] UNIV WASHINGTON,SCH MED,HEARING DEV LAB RL30,SEATTLE,WA 98195
关键词
auditory brainstem; cochlear nucleus; deafferentation; GABA; GAD;
D O I
10.1002/cne.903010411
中图分类号
Q189 [神经科学];
学科分类号
071006 ;
摘要
The effects of unilateral cochlea removal on GABA‐immunoreactive (GABA‐I) terminals in nucleus magnocellularis (NM) of the chick were assessed by immunocytochemical (ICC) techniques. Posthatch chicks (5–8 days old) survived from 1–37 days following unilateral cochlea removal. In the ipsilateral NM, the density of GABA‐I terminals appeared to increase relative to normal controls. 10–37 days after cochlea removal. However, most of that increase could be attributed to a decrease in cell size, cell number, and volume of the nucleus as a result of deafferentation. In the contralateral NM, the density of GABA‐I terminals decreased relative to the ipsilateral NM and to normal animals 1–21 days after cochlea removal. The number of GABA‐I terminals per NM neuron also decreased in the contralateral NM while that in the ipsilateral NM was comparable to normal controls. To ascertain whether these changes represented changes in the number of terminals or in the amount of GABA contained within the terminals, we also examined these terminals using an antibody to glutamic acid decarboxylase (GAD), the biosynthetic enzyme for GABA. Following unilateral cochlea removal, there was no difference in the density of GAD‐I terminals in NM between the two sides of the brain for any of the survival times. Similarly, bilateral cochlea removal had no discernible effect on the density of GABA‐I terminals in NM. These data suggest that unilateral deafferentation may temporarily downregulate the biosynthesis of GABA in the contralateral NM. Copyright © 1990 Wiley‐Liss, Inc.
引用
收藏
页码:643 / 654
页数:12
相关论文
共 38 条
[1]  
BEAR MF, 1985, J NEUROSCI, V5, P1262
[2]  
BORN D E, 1984, Society for Neuroscience Abstracts, V10, P843
[3]   AFFERENT INFLUENCES ON BRAIN-STEM AUDITORY NUCLEI OF THE CHICKEN - NEURON NUMBER AND SIZE FOLLOWING COCHLEA REMOVAL [J].
BORN, DE ;
RUBEL, EW .
JOURNAL OF COMPARATIVE NEUROLOGY, 1985, 231 (04) :435-445
[4]   THE EFFECT OF COCHLEAR NERVE LESION ON THE RELEASE OF GLUTAMATE, ASPARTATE, AND GABA FROM CAT COCHLEAR NUCLEUS, INVITRO [J].
CANZEK, V ;
REUBI, JC .
EXPERIMENTAL BRAIN RESEARCH, 1980, 38 (04) :437-441
[5]   DISTRIBUTION OF GABAERGIC NEURONS AND TERMINALS IN THE AUDITORY-SYSTEM OF THE BARN OWL [J].
CARR, CE ;
FUJITA, I ;
KONISHI, M .
JOURNAL OF COMPARATIVE NEUROLOGY, 1989, 286 (02) :190-207
[6]  
CODE R A, 1987, Society for Neuroscience Abstracts, V13, P543
[7]   DEVELOPMENT OF GABA IMMUNOREACTIVITY IN BRAIN-STEM AUDITORY NUCLEI OF THE CHICK - ONTOGENY OF GRADIENTS IN TERMINAL STAINING [J].
CODE, RA ;
BURD, GD ;
RUBEL, EW .
JOURNAL OF COMPARATIVE NEUROLOGY, 1989, 284 (04) :504-518
[8]   GLYCINE-IMMUNOREACTIVITY IN THE AUDITORY BRAIN-STEM OF THE CHICK [J].
CODE, RA ;
RUBEL, EW .
HEARING RESEARCH, 1989, 40 (1-2) :167-172
[9]  
CODE RA, 1988, 11TH MIDW M ASS RES, P43
[10]  
CODE RA, 1989, 12TH MIDW M ASS RES, P33