dissection and RNA extraction

[dkim at unm.edu]

<Query about dissecting sheep glands and isolating RNA before degradation>

I am not sure exactly what is being described. It looks like you are removing
the glands and putting them in Trizol, then extracting the RNA after you have
accumulated enough . The Trizol solution will not protect RNA in masses of 
tissue until you have ground the tissue up a bit, so the guanidine 
thiocyanate can get to the RNA. If you let the tissue sit for very long, any
RNA inside the tissue mass will be degraded as the cells die.

I used to do RNA extractions from rat organs. In that case, we kept a Dewar
of liquid nitrogen handy. After dissecting out an organ, it went directly into
the nitrogen and stayed frozen until we could grind it up. Frozen tissue was 
put into a 30 ml Corex tube and guanidine thiocyanate solution was added, then
the frozen tissue was homogenized using a Polytron probe.

You might want to adopt this strategy. If liquid nitrogen is not convenient
on the field, I am sure dry ice would work as well.

Daniel Kim    kim at flovax.lanl.gov