Histology FAQ

Staining, Histochemistry and Histotechnology

(Frequently Asked Questions)


Dr. John A. Kiernan
Department of Anatomy and Cell Biology
The University of Western Ontario
London, Canada



FAQ Home > Fixation, freezing etc

Lidocaine in perfusion fixation


Lidocaine can be added to the fixative during perfusion I would appreciate hearing the Lidocaine concentration again.


This is the recipe for lidocaine I used for perfusion-fixing mormyrids (an electric fish):

Lidocaine (= lignocaine = xylocaine) for use in perfusion fixation (Used to relax blood vessels to permit more complete exchange & infiltration of fixative.):

Lidocaine 50 mg per mL, dissolved 95% EtOH (warm to dissolve). Add slowly to perfusion solution with stirring to make final lidocaine solution concentration wanted (e.g. 1mg/mL = 0.1%)

Note: Do not add the lidocaine directly to the perfusion solution, especially if the solution contains salts! The lidocaine will not go into solution.

Philip Oshel
or poshel[AT]hotmail.com)