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Spontaneous BOLD waves - A novel hemodynamic activity in Sprague-Dawley rat brain detected by functional magnetic resonance imaging.

ABSTRACT: We report spontaneous hemodynamic activity termed "Spontaneous BOLD Waves" (SBWs) detected by BOLD fMRI in Sprague-Dawley rats under medetomidine anesthesia. These SBWs, which lasted several minutes, were observed in cortex, thalamus and hippocampus. The SBWs' correlates were undetectable in electrophysiological recordings, suggesting an exclusive gliovascular phenomenon dissociated from neuronal activity. SBWs were insensitive to the NMDA receptors antagonist MK-801 but were inhibited by the ?1-adrenoceptor blocker prazosin. Since medetomidine is a potent agonist of ?2 adrenoceptors, we suggested that imbalance in ?1/?2 receptor-mediated signalling pathways alter the vascular reactivity leading to SBWs. The frequency of SBWs increased with intensity of mechanical lung ventilation despite the stable pH levels. In summary, we present a novel type of propagating vascular brain activity without easily detectable underlying neuronal activity, which can be utilized to study the mechanisms of vascular reactivity in functional and pharmacological MRI and has practical implications for designing fMRI experiments in anesthetized animals.

SUBMITTER: Shatillo A

PROVIDER: S-EPMC6775581 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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Spontaneous BOLD waves - A novel hemodynamic activity in Sprague-Dawley rat brain detected by functional magnetic resonance imaging.

Shatillo Artem A Lipponen Arto A Salo Raimo A RA Tanila Heikki H Verkhratsky Alexei A Giniatullin Rashid R Gröhn Olli H OH

Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism 20180425 10

We report spontaneous hemodynamic activity termed "Spontaneous BOLD Waves" (SBWs) detected by BOLD fMRI in Sprague-Dawley rats under medetomidine anesthesia. These SBWs, which lasted several minutes, were observed in cortex, thalamus and hippocampus. The SBWs' correlates were undetectable in electrophysiological recordings, suggesting an exclusive gliovascular phenomenon dissociated from neuronal activity. SBWs were insensitive to the NMDA receptors antagonist MK-801 but were inhibited by the α1 ...[more]

PMID: 29690796

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Dataset Information

Spontaneous BOLD waves - A novel hemodynamic activity in Sprague-Dawley rat brain detected by functional magnetic resonance imaging.

Publications

Spontaneous BOLD waves - A novel hemodynamic activity in Sprague-Dawley rat brain detected by functional magnetic resonance imaging.

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