Axonal stratification patterns and glutamate-gated conductance mechanisms in zebrafish retinal bipolar cells

被引:62
作者
Connaughton, VP [1 ]
Nelson, R [1 ]
机构
[1] NINDS, Neurophysiol Lab, NIH, Bethesda, MD 20892 USA
来源
JOURNAL OF PHYSIOLOGY-LONDON | 2000年 / 524卷 / 01期
关键词
D O I
10.1111/j.1469-7793.2000.t01-1-00135.x
中图分类号
Q189 [神经科学];
学科分类号
071006 ;
摘要
1. Whole-cell patch recording and puff pipette techniques were used to identify glutamate receptor mechanisms on bipolar cell (BC) dendrites in the zebrafish retinal slice. Recorded neurons were stained with Lucifer Yellow, to correlate glutamate responses with BC morphology. 2. BC axon terminals (ATs) consisted of swellings or varicosities along the axon, as well as at its end. AT stratification patterns identified three regions in the inner plexiform layer (IPL): a thick sublamina a, with three bands of ATs, a narrow terminal-free zone in the mid-IPL, and a thin sublamina b, with two bands of ATs. BCs occurred with ATs restricted to sublamina a (Group a), sublamina b (Group b) or with ATs in both sublaminae (Group a/b). 3. OFF-BCs belonged to Group a or Group alb. These cells responded to glutamate or kainate with a CNQX-sensitive conductance increase. Reversal potential (E-rev) ranged from -0.6 to +18 mV. Bipolar cells stimulated sequentially with both kainate and glutamate revealed a population of glutamate-insensitive, kainate-sensitive cells in addition to cells sensitive to both agonists. 4. ON-BCs responded to glutamate via one of three mechanisms: (a) a conductance decrease with E-rev approximate to 0 mV, mimicked by L-(+)-2-amino-4-phosphonobutyric acid (APB) or trans-1-amino-1,3-cyclopentanedicarboxylic acid (trans-ACPD), (b) a glutamate-gated chloride conductance increase (I-Glu-like) characterized by E-rev greater than or equal to E-cl (where E-cl is the chloride equilibrium potential) and partial blockade by extracellular Li+/Na+ substitution or (c) the activation of both APE and chloride mechanisms simultaneously to produce a response with outward currents at all holding potentials. APE-like responses were found only among BCs in Group b, with a single AT ramifying deep within sublamina b; whereas, cells expressing I-Glu-like currents had one or more ATs, and occurred within Groups b or a/b. 5. Multistratified cells (Group alb) were common and occurred with either ON- or OFF-BC physiology. OFF-BCs typically had one or more ATs in sublamina a and only one AT in sublamina b. In contrast, multistratified ON-BCs had one or more ATs in sublamina b and a single AT ramifying deep in sublamina a. Multistratified ON-BCs expressed the I-Glu-like mechanism only. 6. Visual processing in the zebrafish retina involves at least 13 BC types. Some of these BCs have ATs in both the ON- and OFF-sublaminae, suggesting a significant role for ON- and OFF-inputs throughout the IPL.
引用
收藏
页码:135 / 146
页数:12
相关论文
共 44 条
[1]  
Connaughton V. P., 1998, IOVS, V39, pS982
[2]  
Connaughton Victoria P., 1997, Bulletin of the Mount Desert Island Biological Laboratory, V36, P43
[3]   Immunocytochemical localization of excitatory and inhibitory neurotransmitters in the zebrafish retina [J].
Connaughton, VP ;
Behar, TN ;
Liu, WLS ;
Massey, SC .
VISUAL NEUROSCIENCE, 1999, 16 (03) :483-490
[4]  
Connaughton VP, 1998, EUR J NEUROSCI, V10, P1350
[5]  
DELAVILLA P, 1995, J NEUROSCI, V15, P3571
[6]   Kainate receptors mediate synaptic transmission between cones and "off" bipolar cells in a mammalian retina [J].
DeVries, SH ;
Schwartz, EA .
NATURE, 1999, 397 (6715) :157-160
[7]  
Euler T, 1996, J NEUROSCI, V16, P2934
[8]   NEURONAL ARCHITECTURE OF ON AND OFF PATHWAYS TO GANGLION-CELLS IN CARP RETINA [J].
FAMIGLIETTI, EV ;
KANEKO, A ;
TACHIBANA, M .
SCIENCE, 1977, 198 (4323) :1267-1269
[9]  
GRANT GB, 1995, J NEUROSCI, V15, P3852
[10]   On bipolar cell responses in the teleost retina are generated by two distinct mechanisms [J].
Grant, GB ;
Dowling, JE .
JOURNAL OF NEUROPHYSIOLOGY, 1996, 76 (06) :3842-3849