locus coeruleus & regulation of perfusion - brief notes

 

https://academic.oup.com/brain/advance-article/doi/10.1093/brain/awab054/6242260

 "Animal studies suggest that noradrenergic fibres from the locus coeruleus play a key role in providing trophic support for both astrocytes and neurons, and in suppressing inflammation and oxidative stress.19 Control of microvascular flow by the noradrenergic locus coeruleus might provide part of this trophic support by helping to match oxygen availability to cellular oxidative phosphorylation in brain tissue."

 

https://pubmed.ncbi.nlm.nih.gov/23426667/

"Our data demonstrate that stimulation of the LC activates a broad network of cortical pyramidal cells and interneurons and concomitantly increases cortical perfusion. The hyperemic response virtually disappeared after selective lesioning of the LC–NA system and required activation of α- and β-adrenoreceptors. In addition, the evoked CBF response to the LC–NA system required the release of glutamate and GABA likely from the recruited subsets of pyramidal cells and interneurons and was primarily mediated by epoxyeicosatrienoic acids (EETs) and potassium (K+) fluxes through large-conductance, calcium-operated (BK) and inward-rectifier (Kir) K+ channels. These findings highlight the crosstalk between neurons, astrocytes and arterioles (, , ) in the regulation of the hyperemic response to activation of the LC–NA pathway." 

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