Role of glial cells in regulating retinal blood flow during flicker‐induced hyperemia and systemic hyperoxia‐induced hyporemia in cats

Abstract

SummaryBackgroundTo investigate the role of glial cells in the regulation of retinal circulation in response to flicker stimulation, which is related to neurovascular coupling, and systemic hyperoxia in the retina.MethodsUsing laser Doppler velocimetry, we measured the retinal blood flow (RBF) in first‐order retinal arterioles in anesthetized cats. After intravitreal injection of l‐2‐aminoadipic acid (LAA) as gliotoxic compound, we examined the changes in RBF in response to flicker stimulation of 16 Hz for 3 min and systemic hyperoxia induced by the inhalation of 100% oxygen for 10 min.ResultsThe RBF increased gradually and reached a maximal level after 2–3 min of flicker stimuli in the PBS group. In the LAA‐treated eyes, the increases in RBF during the flicker stimulation were significantly attenuated by one third of those in the control eyes. During hyperoxia, the decreases in RBF in response to hyperoxia were significantly attenuated in the LAA‐treated eyes compared with the control.ConclusionsThe current results suggest that the retinal glial cells play an important role in the regulation of retinal blood flow during Flicker‐Induced Hyperemia and Systemic Hyperoxia‐Induced Hyporemia.