when a substantial cubic cm piece of muscle was sent, tiny 1 and 2 mm bits
of tissue were sectioned.
Gum Tragacanth was used to position the tissueTragacanth
helps get good sections., but it is a bit messy and it is itself a form of
sugar which tends to confound testing for abnormal glycogen.
the tissue for freezing odd heavy metal plugs were used with gum tragacanth and pip of muscle on top of it to insert
into the Isopentane and liquid nitrogen.The mass of metal commands the edge
of the cold effect, which tends to add to the threat of ice crystals.
Gum tragacanth surrounding bits of tissue are placed on
cork to freeze.Cork is a
very good insulator and adds a bit to the chance of ice crystals on the
underside of the tissue.
Isopentane is cooled in theliquid
nitrogen until it gets a little thick.
tissues are sectioned in their native shape which will almost always be
odd, with planes and peeks of tissue. Sections are hardly at their best as
they almost always twist and curl onto the knife due to the erratic angles
presented to the knife. You can see the twisting wayward sections coming
onto the knife in some of the muscle text books.
some strange reason, perhaps due to the suggestion of a tricky leprechaun,
who is still laughing at us for taking himup on it----are picked up on cover
of reagents are kept to the minimum----barely covering the sections on the
The usual buffer for ATP-ase mixtures continues to be the sodium pentobarbital
buffer in the literature.This
takes a controlled substance permit to procure and it’s not worth
the trouble.It’s not
the best buffer for ATP-ase.
Suggestions on better ways will
follow. This is already a lumpy message. .