Nitric oxide imaging in living neuronal tissues using fluorescent probes

Area of Science:

• Neuroscience
• Biochemistry
• Molecular Biology

Background:

• Nitric oxide (NO) is a crucial modulator of neural functions.
• The gaseous nature and short half-life of NO make its spatial distribution and relationship to neuronal activity difficult to resolve.
• Direct, non-invasive visualization of NO in neuronal tissues has been limited by the lack of suitable detection methods.

Purpose of the Study:

• To review recent advances and current trends in the visualization of NO in living neuronal tissues.
• To highlight the potential of specific and non-toxic fluorescent NO indicators for studying NO release dynamics.
• To discuss the utility of these indicators in conjunction with other imaging techniques like calcium-imaging.

Main Methods:

• Development and application of fluorescent indicators that directly detect NO.
• Utilizing indicators that form fluorescent complexes upon reaction with NO.
• Distinguishing NO-sensitive dyes from calcium-sensitive dyes (e.g., Fura-2) for simultaneous imaging.

Main Results:

• Several fluorescent indicators have been developed for direct NO detection.
• Some indicators exhibit promising specificity and low cytotoxicity under physiological conditions.
• These indicators enable the visualization of NO's spatial spread and temporal release patterns.

Conclusions:

• Specific and non-toxic fluorescent NO indicators are powerful tools for NO research in neuronal tissues.
• These indicators facilitate in vitro and in vivo studies of NO release dynamics.
• Combined NO and calcium imaging is possible, offering deeper insights into neural signaling.