Laser uncaging is a temporally and spatially precise means of
releasing biological compounds in vitro.
- The preparation is flooded with inert “caged” biological compound
- A focused laser cleaves a bond between the compound and the “cage”
- The biological compound is released in the area of focus and can now act on its target.
- Depending on the setup, laser uncaging can be restricted to a single dendrite.
We use laser uncaging of caged glutamate to simulate synaptic
release of glutamate from in thalamus slice preparation. Then
we record the response to glutamate stimulation via patch
clamp or extracellular recording.
In the picture below you can see the long silver box of the laser source in
the back right. The laser beam passes through a series of mirrors and through the microscope optics onto a slice of brain tissue. We place electrodes in the slice and record the tissue's response to uncaging.