ePoster

Dissociated neurovascular response to microelectrode stimulation in mouse visual cortex under two-photon microscopy and epifluorescence imaging

Alexandra Yonza, Kayeon Kim, Changsi Cai, Anpan Han, Xiyuan Liu, Shelley Fried
FENS Forum 2024(2024)
Messe Wien Exhibition & Congress Center, Vienna, Austria

Conference

FENS Forum 2024

Messe Wien Exhibition & Congress Center, Vienna, Austria

Resources

Authors & Affiliations

Alexandra Yonza, Kayeon Kim, Changsi Cai, Anpan Han, Xiyuan Liu, Shelley Fried

Abstract

Neuro-implants designed to provide direct brain stimulation are increasingly common in the alleviation of ranged pathologies: from real-time responsive stimulation to hinder seizure activity to the recovery of primitive sight upon the loss of functional visual sensory organs through the direct stimulation of the visual cortex. Though studies of respective neuronal and glial cell types have increased the precision of these artificial stimulation therapies, the study of neurovascular responses to such stimulatory protocols remains comparatively under-studied. A better understanding and quantification of the differences between the hemodynamic responses to more natural stimuli (ie. whisker pad stimulation, visual stimulation, etc) and to artificial intracortical stimulation is necessary to inform the future of neuro-prosthetics. Here, we utilize two-photon and epifluorescence imaging of concurrent calcium-signaling in mural cells and fluorescent plasma staining in transgenic Acta2-GCaMP8.1/mVermilion mice. To illuminate some of the neurovascular response dynamics to direct cortical stimulation, we studied mice under an acute set-up where­ a craniotomy was performed over the right visual cortex and a standard platinum-iridium microelectrode was inserted up to 200 µm into the cortex. Biphasic stimulation was given at 200 Hz for 5 s durations with individual trial currents ranging from 10 - 100 µA. Preliminary results show that upon artificial electrical stimulation, arterioles and arterial capillaries proximal to the microelectrode tip constrict along with increases in calcium-signalling fluorescence of respective pericytes, while vessels peripheral to the site of stimulation (but still contained within the visual cortex) show an opposite pattern of dilation and decreases in calcium-signalling intensities.

Unique ID: fens-24/dissociated-neurovascular-response-24a62299