Comparison of stimulus-evoked cerebral hemodynamics in the awake mouse and under a novel anesthetic regime

Paul S Sharp; Kira Shaw; Luke W Boorman; Samuel S Harris; Aneurin J. Kennerley; Mimoun Azzouz; Jason Berwick

doi:10.1038/srep12621

Comparison of stimulus-evoked cerebral hemodynamics in the awake mouse and under a novel anesthetic regime

Paul S Sharp, Kira Shaw, Luke W Boorman, Samuel S Harris, Aneurin J. Kennerley, Mimoun Azzouz, Jason Berwick

Chemistry

Research output: Contribution to journal › Article › peer-review

Abstract

Neural activity is closely followed by a localised change in cerebral blood flow, a process termed neurovascular coupling. These hemodynamic changes form the basis of contrast in functional magnetic resonance imaging (fMRI) and are used as a correlate for neural activity. Anesthesia is widely employed in animal fMRI and neurovascular studies, however anesthetics are known to profoundly affect neural and vascular physiology, particularly in mice. Therefore, we investigated the efficacy of a novel 'modular' anesthesia that combined injectable (fentanyl-fluanisone/midazolam) and volatile (isoflurane) anesthetics in mice. To characterize sensory-evoked cortical hemodynamic responses, we used optical imaging spectroscopy to produce functional maps of changes in tissue oxygenation and blood volume in response to mechanical whisker stimulation. Following fine-tuning of the anesthetic regime, stimulation elicited large and robust hemodynamic responses in the somatosensory cortex, characterized by fast arterial activation, increases in total and oxygenated hemoglobin, and decreases in deoxygenated hemoglobin. Overall, the magnitude and speed of evoked hemodynamic responses under anesthesia resembled those in the awake state, indicating that the novel anesthetic combination significantly minimizes the impact of anesthesia. Our findings have broad implications for both neurovascular research and longitudinal fMRI studies that increasingly require the use of genetically engineered mice.

Original language	English
Article number	12621
Journal	Scientific Reports
Volume	5
DOIs	https://doi.org/10.1038/srep12621
Publication status	Published - 28 Jul 2015

Access to Document

10.1038/srep12621

Cite this

@article{6acfd69f2c374e7abecd7bf5edf26e72,

title = "Comparison of stimulus-evoked cerebral hemodynamics in the awake mouse and under a novel anesthetic regime",

abstract = "Neural activity is closely followed by a localised change in cerebral blood flow, a process termed neurovascular coupling. These hemodynamic changes form the basis of contrast in functional magnetic resonance imaging (fMRI) and are used as a correlate for neural activity. Anesthesia is widely employed in animal fMRI and neurovascular studies, however anesthetics are known to profoundly affect neural and vascular physiology, particularly in mice. Therefore, we investigated the efficacy of a novel 'modular' anesthesia that combined injectable (fentanyl-fluanisone/midazolam) and volatile (isoflurane) anesthetics in mice. To characterize sensory-evoked cortical hemodynamic responses, we used optical imaging spectroscopy to produce functional maps of changes in tissue oxygenation and blood volume in response to mechanical whisker stimulation. Following fine-tuning of the anesthetic regime, stimulation elicited large and robust hemodynamic responses in the somatosensory cortex, characterized by fast arterial activation, increases in total and oxygenated hemoglobin, and decreases in deoxygenated hemoglobin. Overall, the magnitude and speed of evoked hemodynamic responses under anesthesia resembled those in the awake state, indicating that the novel anesthetic combination significantly minimizes the impact of anesthesia. Our findings have broad implications for both neurovascular research and longitudinal fMRI studies that increasingly require the use of genetically engineered mice.",

author = "Sharp, {Paul S} and Kira Shaw and Boorman, {Luke W} and Harris, {Samuel S} and Kennerley, {Aneurin J.} and Mimoun Azzouz and Jason Berwick",

year = "2015",

month = jul,

day = "28",

doi = "10.1038/srep12621",

language = "English",

volume = "5",

journal = "Scientific Reports",

issn = "2045-2322",

publisher = "Springer",

}

TY - JOUR

T1 - Comparison of stimulus-evoked cerebral hemodynamics in the awake mouse and under a novel anesthetic regime

AU - Sharp, Paul S

AU - Shaw, Kira

AU - Boorman, Luke W

AU - Harris, Samuel S

AU - Kennerley, Aneurin J.

AU - Azzouz, Mimoun

AU - Berwick, Jason

PY - 2015/7/28

Y1 - 2015/7/28

N2 - Neural activity is closely followed by a localised change in cerebral blood flow, a process termed neurovascular coupling. These hemodynamic changes form the basis of contrast in functional magnetic resonance imaging (fMRI) and are used as a correlate for neural activity. Anesthesia is widely employed in animal fMRI and neurovascular studies, however anesthetics are known to profoundly affect neural and vascular physiology, particularly in mice. Therefore, we investigated the efficacy of a novel 'modular' anesthesia that combined injectable (fentanyl-fluanisone/midazolam) and volatile (isoflurane) anesthetics in mice. To characterize sensory-evoked cortical hemodynamic responses, we used optical imaging spectroscopy to produce functional maps of changes in tissue oxygenation and blood volume in response to mechanical whisker stimulation. Following fine-tuning of the anesthetic regime, stimulation elicited large and robust hemodynamic responses in the somatosensory cortex, characterized by fast arterial activation, increases in total and oxygenated hemoglobin, and decreases in deoxygenated hemoglobin. Overall, the magnitude and speed of evoked hemodynamic responses under anesthesia resembled those in the awake state, indicating that the novel anesthetic combination significantly minimizes the impact of anesthesia. Our findings have broad implications for both neurovascular research and longitudinal fMRI studies that increasingly require the use of genetically engineered mice.

AB - Neural activity is closely followed by a localised change in cerebral blood flow, a process termed neurovascular coupling. These hemodynamic changes form the basis of contrast in functional magnetic resonance imaging (fMRI) and are used as a correlate for neural activity. Anesthesia is widely employed in animal fMRI and neurovascular studies, however anesthetics are known to profoundly affect neural and vascular physiology, particularly in mice. Therefore, we investigated the efficacy of a novel 'modular' anesthesia that combined injectable (fentanyl-fluanisone/midazolam) and volatile (isoflurane) anesthetics in mice. To characterize sensory-evoked cortical hemodynamic responses, we used optical imaging spectroscopy to produce functional maps of changes in tissue oxygenation and blood volume in response to mechanical whisker stimulation. Following fine-tuning of the anesthetic regime, stimulation elicited large and robust hemodynamic responses in the somatosensory cortex, characterized by fast arterial activation, increases in total and oxygenated hemoglobin, and decreases in deoxygenated hemoglobin. Overall, the magnitude and speed of evoked hemodynamic responses under anesthesia resembled those in the awake state, indicating that the novel anesthetic combination significantly minimizes the impact of anesthesia. Our findings have broad implications for both neurovascular research and longitudinal fMRI studies that increasingly require the use of genetically engineered mice.

UR - http://www.scopus.com/inward/record.url?scp=84938151129&partnerID=8YFLogxK

U2 - 10.1038/srep12621

DO - 10.1038/srep12621

M3 - Article

C2 - 26218081

AN - SCOPUS:84938151129

SN - 2045-2322

VL - 5

JO - Scientific Reports

JF - Scientific Reports

M1 - 12621

ER -

Comparison of stimulus-evoked cerebral hemodynamics in the awake mouse and under a novel anesthetic regime

Abstract

Access to Document

Other files and links

Cite this