A revisit to staining reagents for neuronal tissues

Area of Science:

• Neuroscience
• Histology
• Biochemistry

Background:

• Historically, staining substances, often small molecules, were essential for discerning healthy from injured neuronal tissues.
• Advancements in chemistry enabled the identification and optimization of staining reagents, enhancing organelle visibility and aiding nerve research.
• Neuronal staining reagents have been pivotal in understanding neuronal organization, degeneration, regeneration, and disease mechanisms in ophthalmology and neuropsychiatric research.

Purpose of the Study:

• To address the lack of a systematic description and readily available information on neuronal staining reagents.
• To provide a comprehensive grouping of staining reagents based on their target location within the nervous system (CNS, PNS, or both).
• To summarize chemical composition, optimal staining conditions, specific neuronal tissue applications, and historical usage of these reagents.

Main Methods:

• Systematic review and categorization of historical and current neuronal staining reagents.
• Grouping reagents based on their primary target: central nervous system (CNS), peripheral nervous system (PNS), or both.
• Summarizing key information including chemical composition, optimal staining conditions, and application for specific neuronal tissues.

Main Results:

• Reagents are categorized into three main groups: CNS, PNS, and those applicable to both.
• The biochemical basis of most staining reagents involves pH-dependent reactions with specific cellular components (organelles, biomolecules).
• Despite limitations like lack of specificity for certain biomolecules (e.g., lipids, metabolites), these reagents effectively enhance contrast and provide microenvironmental context.

Conclusions:

• Neuronal staining reagents remain fundamental tools in neuroscience, aiding in the study of tissue organization and disease pathology.
• This systematic categorization and summary provide valuable guidance for researchers in selecting optimal staining methods for specific neuronal tissues and research goals.
• Future integration of these reagents with advanced techniques like imaging mass spectrometry and kinetic histochemistry promises to deepen our understanding of molecular localization in ophthalmology and vision science.