Mechanisms of Cerebral Vasodilatation During Neuronal Activation by Bicuculline: A Review

AbstractInhibition of RhoA-ROCK pathway is involved in the H2S-induced cerebral vasodilatation and H2S-mediated protection on endothelial cells against oxygen-glucose deprivation/reoxygenation injury. However, the inhibitory mechanism of H2S on RhoA-ROCK pathway is still unclear. The aim of this study was to investigate the target and mechanism of H2S in inhibition of RhoA/ROCK. GST-RhoAwild and GST-RhoAS188A proteins were constructed and expressed, and were used for phosphorylation assay in vitro. Recombinant RhoAwild-pEGFP-N1 and RhoAS188A-pEGFP-N1 plasmids were constructed and transfected into primary hippocampal nerve cells (HNCs) to evaluate the neuroprotective mechanism of endothelial H2S by using transwell co-culture system with endothelial cells from cystathionine-γ-lyase knockout (CSE−/−) mice and 3-mercaptopyruvate sulfurtransferase knockout (3-MST−/−) rats, respectively. We found that NaHS, exogenous H2S donor, promoted RhoA phosphorylation at Ser188 in the presence of cGMP-dependent protein kinase 1 (PKG1) in vitro. Besides, both exogenous and endothelial H2S facilitated the RhoA phosphorylation at Ser188 in HNCs, which induced the reduction of RhoA activity and membrane transposition, as well as ROCK2 activity and expression. To further investigate the role of endothelial H2S on RhoA phosphorylation, we detected H2S release from ECs of CSE+/+ and CSE−/− mice, and 3-MST+/+ and 3-MST−/− rats, respectively, and found that H2S produced by ECs in the culture medium is mainly catalyzed by CSE synthase. Moreover, we revealed that both endothelial H2S, mainly catalyzed by CSE, and exogenous H2S protected the HNCs against hypoxia-reoxygenation injury via phosphorylating RhoA at Ser188.

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Adjustment of Whey:Casein Ratio from 20:80 to 60:40 in Milk Formulation Affects Food Intake and Brainstem and Hypothalamic Neuronal Activation and Gene Expression in Laboratory Mice

Foods ◽

10.3390/foods10030658 ◽

2021 ◽

Vol 10 (3) ◽

pp. 658

Author(s):

Erin L. Wood ◽

David G. Christian ◽

Mohammed Arafat ◽

Laura K. McColl ◽

Colin G. Prosser ◽

...

Keyword(s):

Food Intake ◽

Area Postrema ◽

Energy Levels ◽

Early Gene ◽

Hypothalamic Nucleus ◽

Laboratory Mice ◽

Neuronal Activation ◽

Short Term ◽

Animal Milk ◽

The Impact

Adjustment of protein content in milk formulations modifies protein and energy levels, ensures amino acid intake and affects satiety. The shift from the natural whey:casein ratio of ~20:80 in animal milk is oftentimes done to reflect the 60:40 ratio of human milk. Studies show that 20:80 versus 60:40 whey:casein milks differently affect glucose metabolism and hormone release; these data parallel animal model findings. It is unknown whether the adjustment from the 20:80 to 60:40 ratio affects appetite and brain processes related to food intake. In this set of studies, we focused on the impact of the 20:80 vs. 60:40 whey:casein content in milk on food intake and feeding-related brain processes in the adult organism. By utilising laboratory mice, we found that the 20:80 whey:casein milk formulation was consumed less avidly and was less preferred than the 60:40 formulation in short-term choice and no-choice feeding paradigms. The relative PCR analyses in the hypothalamus and brain stem revealed that the 20:80 whey:casein milk intake upregulated genes involved in early termination of feeding and in an interplay between reward and satiety, such as melanocortin 3 receptor (MC3R), oxytocin (OXT), proopiomelanocortin (POMC) and glucagon-like peptide-1 receptor (GLP1R). The 20:80 versus 60:40 whey:casein formulation intake differently affected brain neuronal activation (assessed through c-Fos, an immediate-early gene product) in the nucleus of the solitary tract, area postrema, ventromedial hypothalamic nucleus and supraoptic nucleus. We conclude that the shift from the 20:80 to 60:40 whey:casein ratio in milk affects short-term feeding and relevant brain processes.

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Memory-specific correlated neuronal activity in higher-order auditory regions of a parrot

Scientific Reports ◽

10.1038/s41598-020-80726-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Ryohei Satoh ◽

Hiroko Eda-Fujiwara ◽

Aiko Watanabe ◽

Yasuharu Okamoto ◽

Takenori Miyamoto ◽

...

Keyword(s):

Neuronal Activity ◽

Higher Order ◽

Auditory Memory ◽

Neuronal Activation ◽

Contact Calls ◽

Contrast Exposure ◽

Auditory Region ◽

Neuronal Representation ◽

Specific Association ◽

Positive Correlations

AbstractMale budgerigars (Melopsittacus undulatus) are open-ended learners that can learn to produce new vocalisations as adults. We investigated neuronal activation in male budgerigars using the expression of the protein products of the immediate early genes zenk and c-fos in response to exposure to conspecific contact calls (CCs: that of the mate or an unfamiliar female) in three subregions (CMM, dNCM and vNCM) of the caudomedial pallium, a higher order auditory region. Significant positive correlations of Zenk expression were found between these subregions after exposure to mate CCs. In contrast, exposure to CCs of unfamiliar females produced no such correlations. These results suggest the presence of a CC-specific association among the subregions involved in auditory memory. The caudomedial pallium of the male budgerigar may have functional subdivisions that cooperate in the neuronal representation of auditory memory.

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Exploring the possibility of applying different neuronal activation functions to a single-circuit ACS

Journal of Physics Conference Series ◽

10.1088/1742-6596/1889/2/022007 ◽

2021 ◽

Vol 1889 (2) ◽

pp. 022007

Author(s):

A S Pomogaev ◽

D A Dementev ◽

D M Krasnenko ◽

A S Shtylenko

Keyword(s):

Activation Functions ◽

Neuronal Activation

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