Developmental changes in NMDA receptor-mediated visual activity in the rat superior colliculus, and the effect of dark rearing

1998 ◽  
Vol 120 (3) ◽  
pp. 335-344 ◽  
Author(s):  
K. E. Binns ◽  
T. E. Salt
Keyword(s):  
Nmda Receptor ◽  
Superior Colliculus ◽  
Developmental Changes ◽  
Visual Activity ◽  
Dark Rearing

Effect of longer periods of dark rearing on NMDA receptors in cat visual cortex

1994 ◽  
Vol 72 (3) ◽  
pp. 1220-1226 ◽  
Author(s):  
D. Czepita ◽  
S. N. Reid ◽  
N. W. Daw
Keyword(s):  
Visual Cortex ◽  
Nmda Receptor ◽  
Firing Rate ◽  
Spontaneous Activity ◽  
Visual Response ◽  
Visual Responses ◽  
Level Of Activity ◽  
Direction Of Movement ◽  
Excitatory Drive ◽  
Dark Rearing

1. Cats were reared in the dark to 3, 5, and 11 mo. We studied the N-methyl-D-aspartate (NMDA) receptor contribution to the visual response in the cortex, defined as the percentage reduction in visual response after application of 2-amino-5-phosphonovaleric acid (APV). We also studied the firing rate in response to the optimal visual stimulus and the spontaneous activity. We made comparisons of all these properties between light-reared and dark-reared animals. 2. The NMDA receptor contribution to the visual response in layers IV, V, and VI of dark-reared animals was substantially above that in light-reared animals at all ages tested. 3. The specificity of receptive field properties in dark-reared animals showed some degeneration between 6 wk and 3 mo of age. At > or = 3 mo, almost no cells were specific for orientation and direction of movement. 4. Firing rate was lower in dark-reared animals at all ages, suggesting a decrease in excitatory drive to the visual cortex. 5. Spontaneous activity was equal in dark- and light-reared animals, suggesting that the overall level of activity (including visual responses as well as spontaneous activity) in light-reared animals is higher than in dark-reared animals. This should tend to upregulate glutamate receptors in general in dark-reared animals.

scholarly journals What the Brain Stem Tells the Frontal Cortex. I. Oculomotor Signals Sent From Superior Colliculus to Frontal Eye Field Via Mediodorsal Thalamus

2004 ◽  
Vol 91 (3) ◽  
pp. 1381-1402 ◽  
Author(s):  
Marc A. Sommer ◽  
Robert H. Wurtz
Keyword(s):  
Superior Colliculus ◽  
Frontal Cortex ◽  
Brain Stem ◽  
Signal Transmission ◽  
Frontal Eye Field ◽  
Visual Responses ◽  
Mediodorsal Thalamus ◽  
Visual Activity ◽  
Eye Field ◽  
The Brain

Neuronal processing in cerebral cortex and signal transmission from cortex to brain stem have been studied extensively, but little is known about the numerous feedback pathways that ascend from brain stem to cortex. In this study, we characterized the signals conveyed through an ascending pathway coursing from the superior colliculus (SC) to the frontal eye field (FEF) via mediodorsal thalamus (MD). Using antidromic and orthodromic stimulation, we identified SC source neurons, MD relay neurons, and FEF recipient neurons of the pathway in Macaca mulatta. The monkeys performed oculomotor tasks, including delayed-saccade tasks, that permitted analysis of signals such as visual activity, delay activity, and presaccadic activity. We found that the SC sends all of these signals into the pathway with no output selectivity, i.e., the signals leaving the SC resembled those found generally within the SC. Visual activity arrived in FEF too late to contribute to short-latency visual responses there, and delay activity was largely filtered out in MD. Presaccadic activity, however, seemed critical because it traveled essentially unchanged from SC to FEF. Signal transmission in the pathway was fast (∼2 ms from SC to FEF) and topographically organized (SC neurons drove MD and FEF neurons having similarly eccentric visual and movement fields). Our analysis of identified neurons in one pathway from brain stem to frontal cortex thus demonstrates that multiple signals are sent from SC to FEF with presaccadic activity being prominent. We hypothesize that a major signal conveyed by the pathway is corollary discharge information about the vector of impending saccades.

scholarly journals Laminar Specific Distribution of Lateral Excitatory Connections in the Rat Superior Colliculus

2004 ◽  
Vol 92 (6) ◽  
pp. 3500-3510 ◽  
Author(s):  
Yasuhiko Saito ◽  
Tadashi Isa
Keyword(s):  
Signal Processing ◽  
Nmda Receptor ◽  
Synaptic Transmission ◽  
Superior Colliculus ◽  
Neuronal Population ◽  
Wide Field ◽  
Specific Distribution ◽  
Excitatory Network ◽  
Voltage Dependent ◽  
Whole Cell Recordings

Premovement activities in neurons in the intermediate gray layer [stratum griseum intermediale (SGI)] of the mammalian superior colliculus (SC) are essential for initiation of orienting behaviors such as saccades. Our previous study demonstrated that burst activities are induced by synchronous activation of SGI neurons communicating within a local excitatory network, which depends on NMDA-receptor–dependent synaptic transmission and release from GABAA inhibition. Furthermore, dual whole cell recordings from adjacent neurons in SGI revealed that application of 10 μM bicuculline (Bic) and reduction of extracellular Mg2+ concentration (to 0.1 mM) induce spontaneous depolarization that is synchronous between neuron pairs, suggesting the recruitment of a large number of neurons communicating through intense excitatory connections. In the present study, we investigated the properties of synchronous depolarization and the fundamental structure of the lateral excitatory network that recruits a neuronal population in SC to synchronous activation, by analyzing the synchronicity of spontaneous depolarization induced in the presence of Bic plus low Mg2+. We found that 1) spontaneous depolarization exhibits bidirectional horizontal propagation among the SGI neuron pairs; 2) induction of spontaneous depolarization is not caused by activation of intrinsic voltage-dependent conductances; 3) neurons exposed to low Mg2+ alone exhibit spontaneous depolarization, although in this case the depolarization is less synchronous; and 4) neurons exposed to Bic alone exhibit synchronous depolarization, but less frequently than those exposed to both Bic and low Mg2+. Analysis of the synchronicity of spontaneous depolarization indicates that the distribution of lateral excitatory connections is markedly different among layers of SC; the SGI neurons form extensive lateral excitatory connections, whereas they are sparse or limited within subsets of neurons in the stratum griseum superficiale (SGS). Wide-field vertical neurons in the stratum opticum have features intermediate between neurons in the SGS and SGI. Such differences in the structure of lateral excitatory connections may reflect the different way signal processing is achieved in each layer of SC.

Developmental changes of nitric oxide synthase in the rat superior colliculus

1995 ◽  
Vol 42 (5) ◽  
pp. 633-637 ◽  
Author(s):  
F. Tenório ◽  
A. Giraldi-Guimarães ◽  
R. Mendez-Otero
Keyword(s):  
Nitric Oxide ◽  
Nitric Oxide Synthase ◽  
Superior Colliculus ◽  
Developmental Changes ◽  
Oxide Synthase

Developmental Changes of Synaptic and Extrasynaptic NMDA Receptor Expression in Rat Cerebellar Neurons In Vitro

2017 ◽  
Vol 64 (2) ◽  
pp. 300-311 ◽  
Author(s):  
Dmitry A. Sibarov ◽  
Yulia D. Stepanenko ◽  
Ivan V. Silantiev ◽  
Polina A. Abushik ◽  
Tatiana V. Karelina ◽  
...  
Keyword(s):  
Nmda Receptor ◽  
Receptor Expression ◽  
Developmental Changes ◽  
Cerebellar Neurons
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