Acetylcholinesterase Activity Staining in Freshwater Planarians

Area of Science:

• Neuroscience
• Toxicology
• Biochemistry

Background:

• Acetylcholinesterase (AChE) is a key enzyme regulating neurotransmission.
• AChE inhibition by pesticides is a significant toxicological concern.
• Freshwater planarians are a viable model for in vivo pesticide studies.

Purpose of the Study:

• To develop a straightforward protocol for visualizing AChE activity in whole-mount planarians.
• To provide an alternative to the biochemical Ellman assay for AChE activity quantification.
• To establish a new method for evaluating AChE inhibition in planarian models.

Main Methods:

• Planarians were fixed and stained using acetylthiocholine as a substrate.
• Activity staining was performed using standard laboratory equipment.
• Imaging of stained planarians was conducted using a light microscope.

Main Results:

• The developed protocol allows for the visualization of AChE activity in individual planarians within hours.
• Exposure to an organophosphorus pesticide resulted in a loss of AChE staining.
• The method successfully demonstrated AChE inhibition.

Conclusions:

• A simple, accessible method for visualizing AChE activity in planarians has been established.
• This technique offers a qualitative tool for assessing AChE inhibition due to chemical exposure or genetic manipulation.
• The protocol facilitates mechanistic studies of the cholinergic system in planarian models.