Long-term impairment of neurovascular coupling following experimental subarachnoid hemorrhage

Balbil, Matilde; Vega, Max Jativa; Lourbopoulos, Athanasios; Terpolilli, Nicole A.; Plesnila, Nikolaus (2019): Long-term impairment of neurovascular coupling following experimental subarachnoid hemorrhage. In: Journal of Cerebral Blood Flow and Metabolism, Vol. 40, No. 6: pp. 1193-1202

Abstract

CO2-reactivity and neurovascular coupling are sequentially lost within the first 24 h after subarachnoid hemorrhage (SAH). Whether and when these impairments recover is not known. Therefore, we investigated the reactivity of pial and intraparenchymal vessels by in vivo two-photon microscopy one month after experimental SAH. C57BL/6 mice were subjected to either sham surgery or SAH by filament perforation. One month later, cerebral blood flow following CO2-challenge and forepaw stimulation was assessed by laser Doppler fluxmetry. Diameters of pial and intraparenchymal arterioles were quantified by in vivo two-photon microscopy. One month after SAH, pial and parenchymal vessels dilated in response to CO2. Neurovascular coupling was almost completely absent after SAH: vessel diameter did not change upon forepaw stimulation compared to a 20% increase in sham-operated mice. The current results demonstrate that neurovascular function differentially recovers after SAH: while CO2-reactivity normalizes within one month after SAH, neurovascular coupling is still absent. These findings show an acute and persistent loss of neurovascular coupling after SAH that may serve as a link between early brain injury and delayed cerebral ischemia, two distinct pathophysiological phenomena after SAH that were so far believed not to be directly related.

• Item Type: Journal article
• Faculties: Medicine
• Research Centers: Graduate School of Systemic Neurosciences (GSN)
• Subjects: 600 Technology > 610 Medicine and health; 500 Science > 500 Science
• ISSN: 0271-678X
• Language: English