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Postnov, D.

Publications and source records attributed to Postnov, D..

2 recordsLinked to original sources

Pilot identification of the Live-1/Prox-1 expressing lymphatic vessels and lymphatic elements in the unaffected and affected human brain

We report here a pilot identification of the presence of the lumenized Lyve-1/Prox-1-expressing vessels with distinct walls composed of a single endothelial layer in the unaffected brain and with intraventricular hemorrhages. These lymphatic vessels (LVs) have valves and an undulating shape in the distal region that is the classical characteristic of lymphatic precollectors. Furthermore, we identified Lyve-1/Prox-1-expressing lymphatic elements in the enlarged perivascular spaces. These pioneering results might be a revolutionary step in our understanding of anatomy and physiology of the cerebral lymphatics and stimulate a reassessment of basic assumptions in the aetiology of brain diseases associated with lymphatic dysfunction. The discovery of the cerebral LVs is a crucial step in the development of breakthrough technologies of modulations of lymphatic removing of toxins and blood from the brain. One Sentence SummaryLyve1/Prox1-expressing lymphatic vessels and elements in the unaffected and affected human brain.

neuroscience↗

Modification of oxygen consumption and blood flow in mouse somatosensory cortex by cell-type-specific neuronal activity

Gamma activity arises from the interplay between pyramidal neurons and fast-spiking parvalbumin (PV) interneurons, is an integral part of higher cognitive functions and is assumed to contribute importantly to brain metabolic responses. Cerebral metabolic rate of oxygen (CMRO2) responses were evoked by optogenetic stimulation of cortical PV interneurons and pyramidal neurons. We found that CMRO2 responses depended on neuronal activation, but not on the power of gamma activity induced by optogenetic stimulation. This implies that evoked gamma activity per se is not energy demanding. Optogenetic stimulation of PV interneurons during somatosensory stimulation reduced excitatory neuronal activity but did not potentiate O2 consumption as previously hypothesized. In conclusion, our data suggest that activity-driven CMRO2 responses depend on neuronal excitation rather than the cerebral rhythmic activity they induce. Excitation of both excitatory and inhibitory neurons requires energy, but inhibition of cortical excitatory neurons by interneurons does not potentiate activity-driven energy consumption.

neuroscience↗