Staining normal and experimental motor nerve terminals with tetrazolium salts

Area of Science:

• Neuroscience
• Histology
• Biochemistry

Background:

• Nitroblue tetrazolium (NBT) is used for staining motor nerve terminals and unmyelinated axons in vertebrate skeletal muscle.
• Traditional NBT staining results in undesirable background coloration of connective tissues, obscuring nerve structures.

Purpose of the Study:

• To improve the specificity and quality of nerve terminal and axon staining in skeletal muscle.
• To overcome the limitations of background staining associated with conventional NBT methods.

Main Methods:

• Separation of the tetrazolium salt's binding step from its subsequent reduction.
• Utilizing tetranitroblue tetrazolium (TNBT) for improved nerve terminal staining.
• Incorporating counterstaining and postfixation with osmium tetroxide for enhanced tissue preservation.

Main Results:

• The uncoupled binding and reduction procedure significantly improved nerve terminal staining.
• Enhanced visualization of motor nerve terminals and unmyelinated axons was achieved.
• Overall tissue preservation was superior compared to traditional NBT staining.

Conclusions:

• The modified NBT staining technique provides superior staining of motor nerve terminals and axons.
• This method is compatible with acetylcholinesterase staining, allowing for combined analysis.
• The procedure is effective for both experimentally manipulated and diseased muscle preparations.