Transcranial real-time in vivo recording of electrophysiological neural activity in the rodent brain with near-infrared photoacoustic voltage-sensitive dye imaging

Kang, J.; Zhang, H. K.; Kadam, S. D.; Julie, F.; Valentine, H.; Kang, J. U.; Rahmim, A.; Gjedde, A.; Loew, L. M.; Wong, D. F.; Boctor, E. M.

doi:10.1101/202408

bioRxiv · 10.1101/202408

Transcranial real-time in vivo recording of electrophysiological neural activity in the rodent brain with near-infrared photoacoustic voltage-sensitive dye imaging

Kang, J.·Zhang, H. K.·Kadam, S. D.·Julie, F.·Valentine, H.·Kang, J. U.·Rahmim, A.·Gjedde, A.·Loew, L. M.·Wong, D. F.·Boctor, E. M.

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Abstract

Minimally-invasive monitoring of electrophysiological neural activities in real-time--that enables quantification of neural functions without a need for invasive craniotomy and the longer time constants of fMRI and PET--presents a very challenging yet significant task for neuroimaging. In this paper, we present in vivo functional PA (fPA) imaging of chemoconvulsant rat seizure model with intact scalp using a fluorescence quenching-based cyanine voltage-sensitive dye (VSD) characterized by a lipid vesicle model mimicking different levels of membrane potential variation. The framework also involves use of a near-infrared VSD delivered through the blood-brain barrier (BBB), opened by pharmacological modulation of adenosine receptor signaling. Our normalized time-frequency analysis presented in vivo VSD response in the seizure group significantly distinguishable from those of the control groups at sub-mm spatial resolution. Electroencephalogram (EEG) recording confirmed the changes of severity and frequency of brain activities, induced by chemoconvulsant seizures of the rat brain. The findings demonstrate that the near-infrared fPA VSD imaging is a promising tool for in vivo recording of brain activities through intact scalp, which would pave a way to its future translation.

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Kang, J., Zhang, H. K., Kadam, S. D., Julie, F., Valentine, H., Kang, J. U., Rahmim, A., Gjedde, A., Loew, L. M., Wong, D. F., Boctor, E. M.. 2017-10-16. Transcranial real-time in vivo recording of electrophysiological neural activity in the rodent brain with near-infrared photoacoustic voltage-sensitive dye imaging. https://doi.org/10.1101/202408

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