Microdialysis has been used for over 30 years to sample molecules within the extracellular space of a tissue, including brain and muscle. One advantage of the technique is that it can be performed in awake, behaving animals so that longitudinal measurements can be performed under physiological conditions. Brain interstitial fluid (ISF) can be sampled hourly in living mice using microdialysis. The technique not only determines the magnitude of change in the target, but also the kinetics of that change.
The Core was originally designed to screen compounds for their ability to reduce brain interstitial fluid (ISF) Aβ levels. Brain ISF can be sampled hourly in living mice using microdialysis. The technique not only determines the magnitude that a compound alters ISF Aβ, but also the kinetics of that change.
ISF Aβ measurements
Determine the effect of compounds on ISF Aβ levels in living mice. Compounds can be administered directly to the brain via the microdialysis probe, injected intraperitoneal or subcutaneous, or given orally. Brain ISF Aβ levels are typically sampled in 1 hour increments over 36-48 hours. Each mouse can receive a single dose, a gradual escalation of several doses, or can receive several distinct compounds.
Measurements of small molecules, peptides
In addition to Abeta, we are able to detect a variety of molecules and proteins within the brain ISF, including small molecules such as glutamate and urea as well as peptides such as orexin. We are always interested in measuring other targets as required by a scientific project. We are equipped to perform microdialysis in both mice and rats.
Aβ40 and Aβ42 can be measured by sandwich ELISA.
Other analytes can also be measured within the microdialysis samples. For example, compounds levels can be assessed to determine brain exposure following systemic administration.