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Application of Genetically Encoded Fluorescent Nitric Oxide (NO•) Probes, the geNOps, for Real-time Imaging of NO• Signals in Single Cells
Published on: March 16, 2017
Interaction between nitric oxide synthase inhibitor induced oscillations and the activation flow coupling response
Beau M Ances1, Joel H Greenberg, John A Detre
1Department of Neurology, Washington University in St. Louis, 660 South Euclid Avenue, St. Louis, MO 63110, USA. bances@wustl.edu
Brain Research
|November 11, 2009
Summary
Nitric oxide (NO) influences brain blood flow responses to stimulation. Inhibiting nitric oxide synthase with L-NNA altered cerebral blood flow (CBF) oscillations and modulated the activation-flow coupling (AFC) response, suggesting NO
Area of Science:
- Neuroscience
- Physiology
- Cerebrovascular Regulation
Background:
- The activation-flow coupling (AFC) response describes how neural activity influences cerebral blood flow (CBF).
- Nitric oxide (NO) is a known vasodilator implicated in regulating CBF.
- The precise role of NO in AFC dynamics, particularly its interaction with intrinsic vasomotion, remains incompletely understood.
Purpose of the Study:
- To investigate the role of nitric oxide (NO) in the activation-flow coupling (AFC) response.
- To examine the impact of nitric oxide synthase (NOS) inhibition on cerebral blood flow (CBF) oscillations and AFC.
- To elucidate the interaction between NO-modulated vasomotion and AFC.
Main Methods:
- Utilized signal-averaged laser Doppler (LD) flowmetry to measure calculated cerebral blood flow (CBF).
- Administered N(G)-nitro-L-arginine (L-NNA), a non-selective NOS inhibitor, to investigate NO's role.
- Applied periodic electrical forepaw stimulation with varying durations and intervals to assess AFC.
Main Results:
- L-NNA administration induced characteristic low-frequency vasomotion oscillations (0.17 Hz) in CBF, synchronous within hemispheres.
- Inhibition of NO synthesis reduced the AFC response magnitude for longer stimuli and longer inter-stimulus intervals.
- Conversely, L-NNA augmented the AFC response magnitude for shorter stimuli and shorter inter-stimulus intervals, particularly near the frequency of induced vasomotion.
Conclusions:
- Nitric oxide (NO) plays a modulatory role in the activation-flow coupling (AFC) response.
- NO influences the dynamic interplay between cerebral blood flow oscillations and neural activation.
- These findings suggest NO modulates the effects of other vasodilators involved in vasomotion and AFC.
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