scholarly journals Clustering and control for adaptation uncovers time-warped spike time patterns in cortical networks in vivo

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
James B. Isbister ◽  
Vicente Reyes-Puerta ◽  
Jyh-Jang Sun ◽  
Illia Horenko ◽  
Heiko J. Luhmann
Keyword(s):  
Spike Time ◽  
Time Pattern ◽  
Stimulus Response ◽  
Adult Rat ◽  
State Dependent ◽  
Time Patterns ◽  
Time Encoding ◽  
Rat Somatosensory Cortex ◽  
Pattern Modulation

AbstractHow information in the nervous system is encoded by patterns of action potentials (i.e. spikes) remains an open question. Multi-neuron patterns of single spikes are a prime candidate for spike time encoding but their temporal variability requires further characterisation. Here we show how known sources of spike count variability affect stimulus-evoked spike time patterns between neurons separated over multiple layers and columns of adult rat somatosensory cortex in vivo. On subsets of trials (clusters) and after controlling for stimulus-response adaptation, spike time differences between pairs of neurons are “time-warped” (compressed/stretched) by trial-to-trial changes in shared excitability, explaining why fixed spike time patterns and noise correlations are seldom reported. We show that predicted cortical state is correlated between groups of 4 neurons, introducing the possibility of spike time pattern modulation by population-wide trial-to-trial changes in excitability (i.e. cortical state). Under the assumption of state-dependent coding, we propose an improved potential encoding capacity.

scholarly journals Plasticity of Horizontal Connections at a Functional Border in Adult Rat Somatosensory Cortex

2009 ◽  
Vol 2009 ◽  
pp. 1-15 ◽  
Author(s):  
Sally A. Marik ◽  
Peter W. Hickmott
Keyword(s):  
Synaptic Plasticity ◽  
Low Frequency ◽  
Cortical Reorganization ◽  
Adult Rat ◽  
Horizontal Connections ◽  
Frequency Stimulation ◽  
Rat Somatosensory Cortex ◽  
Cortical Regions

Horizontal connections in superficial cortical layers integrate information across sensory maps by connecting related functional columns. It has been hypothesized that these connections mediate cortical reorganization via synaptic plasticity. However, it is not known if the horizontal connections from discontinuous cortical regions can undergo plasticity in the adult. Here we located the border between two discontinuous cortical representations in vivo and used either pairing or low-frequency stimulation to induce synaptic plasticity in the horizontal connections surrounding this border in vitro. Individual neurons revealed significant and diverse forms of synaptic plasticity for horizontal connections within a continuous representation and discontinuous representations. Interestingly, both enhancement and depression were observed following both plasticity paradigms. Furthermore, plasticity was not restricted by the border's presence. Depolarization in the absence of synaptic stimulation also produced synaptic plasticity, but with different characteristics. These experiments suggest that plasticity of horizontal connections may mediate functional reorganization.

scholarly journals In vivo phosphorylation sites in fetal and adult rat tau.

1993 ◽  
Vol 268 (34) ◽  
pp. 25712-25717
Author(s):  
A Watanabe ◽  
M Hasegawa ◽  
M Suzuki ◽  
K Takio ◽  
M Morishima-Kawashima ◽  
...  
Keyword(s):  
Phosphorylation Sites ◽  
Adult Rat

scholarly journals In vivo sucrase-isomaltase and lactase-phlorizin hydrolase turnover in the fed adult rat

1993 ◽  
Vol 268 (18) ◽  
pp. 13609-13616
Author(s):  
M.A. Dudley ◽  
D.L. Hachey ◽  
A. Quaroni ◽  
T.W. Hutchens ◽  
B.L. Nichols ◽  
...  
Keyword(s):  
Adult Rat

A Detailed Examination of the in vivo and in vitro Effects of ACTH on Gonadotropin Secretion in the Adult Rat

1985 ◽  
Vol 40 (4) ◽  
pp. 297-302 ◽  
Author(s):  
David R. Mann ◽  
Diane Evans ◽  
Festus Edoimioya ◽  
Freja Kamel ◽  
George M. Butterstein
Keyword(s):  
Detailed Examination ◽  
Gonadotropin Secretion ◽  
Adult Rat ◽  
In Vitro Effects

Stable incorporation of a bacterial gene into adult rat skeletal muscle in vivo

1990 ◽  
Vol 258 (3) ◽  
pp. C578-C581 ◽  
Author(s):  
D. B. Thomason ◽  
F. W. Booth
Keyword(s):  
Skeletal Muscle ◽  
Leukemia Virus ◽  
Rat Skeletal Muscle ◽  
Bacterial Gene ◽  
Muscle Gene Expression ◽  
Adult Rat ◽  
Foreign Genes ◽  
Muscle Gene ◽  
Beta Galactosidase

We have developed a novel technique to incorporate and stably express foreign genes in adult rat skeletal muscle in vivo. Endogeneous satellite cells in skeletal muscle regenerating from bupivacaine damage were infected with an injected retrovirus containing the Escherichia coli beta-galactosidase gene under the promoter control of the Moloney murine leukemia virus long-terminal repeat. Constitutive and stable expression of beta-galactosidase activity was observed in muscle fibers after 6 days and 1 mo of muscle regeneration. Two patterns of expression were observed, diffuse expression within fibers and focal expression associated with the sarcolemma. This technique will allow future experiments with muscle-specific genes and promoters to study the physiological regulation of skeletal muscle gene expression in the intact adult mammal. Furthermore, the technique of stimulating stem cell proliferation to allow retroviral-mediated gene transfer may be generally applicable to other tissues.

scholarly journals Neural and genetic degeneracy underlies Caenorhabditis elegans feeding behavior

2014 ◽  
Vol 112 (4) ◽  
pp. 951-961 ◽  
Author(s):  
Nicholas F. Trojanowski ◽  
Olivia Padovan-Merhar ◽  
David M. Raizen ◽  
Christopher Fang-Yen
Keyword(s):  
Caenorhabditis Elegans ◽  
Neural Circuit ◽  
Dependent Manner ◽  
State Dependent ◽  
Excitatory Pathways ◽  
Genetic Mechanisms ◽  
Genetic Level ◽  
Pharyngeal Pumping ◽  
Robust Network

Degenerate networks, in which structurally distinct elements can perform the same function or yield the same output, are ubiquitous in biology. Degeneracy contributes to the robustness and adaptability of networks in varied environmental and evolutionary contexts. However, how degenerate neural networks regulate behavior in vivo is poorly understood, especially at the genetic level. Here, we identify degenerate neural and genetic mechanisms that underlie excitation of the pharynx (feeding organ) in the nematode Caenorhabditis elegans using cell-specific optogenetic excitation and inhibition. We show that the pharyngeal neurons MC, M2, M4, and I1 form multiple direct and indirect excitatory pathways in a robust network for control of pharyngeal pumping. I1 excites pumping via MC and M2 in a state-dependent manner. We identify nicotinic and muscarinic receptors through which the pharyngeal network regulates feeding rate. These results identify two different mechanisms by which degeneracy is manifest in a neural circuit in vivo.

Effects of hypophysectomy and subsequent FSH and testosterone treatment on inhibin production by adult rat testes

1985 ◽  
Vol 105 (1) ◽  
pp. 1-6 ◽  
Author(s):  
C. L. Au ◽  
D. M. Robertson ◽  
D. M. de Kretser
Keyword(s):  
Seminiferous Tubule ◽  
Hormonal Control ◽  
Human Chorionic Gonadotrophin ◽  
Experimental Conditions ◽  
Adult Rats ◽  
Adult Rat ◽  
Fluid Production ◽  
Tubule Fluid

ABSTRACT The hormonal control of inhibin production by adult rat testes was investigated using an in-vitro inhibin bioassay validated for the measurement of inhibin activity in charcoal-treated rat testicular extracts. The effect of hypophysectomy examined at 16 h, 3, 7 and 42 days after surgery showed a decrease in testicular inhibin content and seminiferous tubule fluid production by 7 days and a decrease in inhibin production by 42 days. Serum FSH and LH were suppressed 3 days after surgery. In 30-day chronically hypophysectomized adult rats treated for 3 days with twice daily s.c. injections of (a) human FSH (hFSH, 22 i.u./rat per day), (b) testosterone (5 mg/rat per day), (c) hFSH + testosterone (same doses as a and b), or (d) human chorionic gonadotrophin (hCG, 12 i.u./rat per day), hFSH or hFSH and testosterone stimulated an increase in testicular inhibin content but not in inhibin production or tubule fluid production. Testosterone and hCG had no effect on these parameters. It is concluded that in vivo, FSH alone stimulates an increase in testicular inhibin content. The failure to observe an increase in inhibin production in vivo is attributed to the suppression of seminiferous tubule fluid production under the same experimental conditions. J. Endocr. (1985) 105, 1–6

Short-Term Plasticity at Inhibitory Synapses in Rat Striatum and Its Effects on Striatal Output

2001 ◽  
Vol 85 (5) ◽  
pp. 2088-2099 ◽  
Author(s):  
John S. Fitzpatrick ◽  
Garnik Akopian ◽  
John P. Walsh
Keyword(s):  
Action Potentials ◽  
Brain Slices ◽  
Current Injection ◽  
Inhibitory Synapses ◽  
Rat Striatum ◽  
Short Term ◽  
Short Term Plasticity ◽  
Adult Rat ◽  
Glutamate Receptor Antagonists

Two forms of short-term plasticity at inhibitory synapses were investigated in adult rat striatal brain slices using intracellular recordings. Intrastriatal stimulation in the presence of the ionotropic glutamate receptor antagonists 6-cyano-7-nitroquinoxaline-2,3-dione (20 μM) andd,l-2-amino-5-phosphonovaleric acid (50 μM) produced an inhibitory postsynaptic potential (IPSP) that reversed polarity at −76 ± 1 (SE) mV and was sensitive to bicuculline (30 μM). The IPSP rectified at hyperpolarized membrane potentials due in part to activation of K+ channels. The IPSP exhibited two forms of short-term plasticity, paired-pulse depression (PPD) and synaptic augmentation. PPD lasted for several seconds and was greatest at interstimulus intervals (ISIs) of several hundred milliseconds, reducing the IPSP to 80 ± 2% of its control amplitude at an ISI of 200 ms. Augmentation of the IPSP, elicited by a conditioning train of 15 stimuli applied at 20 Hz, was 119 ± 1% of control when sampled 2 s after the conditioning train. Augmentation decayed with a time constant of 10 s. We tested if PPD and augmentation modify the ability of the IPSP to prevent the generation of action potentials. A train of action potentials triggered by a depolarizing current injection of constant amplitude could be interrupted by stimulation of an IPSP. If this IPSP was the second in a pair of IPSPs, it was less effective in blocking spikes due to PPD. By contrast, augmented IPSPs were more effective in blocking spikes. The same results were achieved when action potentials were triggered by a depolarizing current injection of varying amplitude, a manipulation that produces nearly identical spike times from trial to trial and approximates the in vivo behavior of these neurons. These results demonstrate that short-term plasticity of inhibition can modify the output of the striatum and thus may be an important component of information processing during behaviors that involve the striatum.

Sign in / Sign up

Export Citation Format

Share Document