[Histonet] marking liver in vivo for later collection

[Caroline Bass]

Hello everyone,

This may be more of a surgery question than histology, but as the 
knowledge on this forum seems rather diverse I was hoping someone could 
help me.

I am injecting various viral vectors directly into the liver (i.e. 
intrahepatically) of mice.  As you can imagine, the incision for this 
injection is rather small compared to the entire liver.  When I collect 
the tissue, it is sometimes difficult to determine where the injection 
was made.  As my virus doesn't seem to diffuse very far from the 
injection site, I would like to mark the injection site in some way.  
Right now when I collect the tissue I can usually narrow it down to the 
correct lobe.  Is there any way to mark the liver at the time of 
injection so that collection is easy later?  I have heard of surgeons 
burning their initials into tissue that they were removing for later 
analysis.  Could this be possible, perhaps just a small prick with a 
heated probe?

I don't want to do anything that is unethical, could compromise the 
health of the animal, or cause undue stress or pain.  Any advice would 
be appreciated.  It is so much easier with the brain where you can see 
the site of injection and follow a needle track.

Thanks,

Caroline Bass