Section Cutting and Staining: A practical introduction to histological methods for students and practitionersColman, Walter S.
Science
Section Cutting and Staining: A practical introduction to histological methods for students and practitioners
Colman, Walter S.
Microscopy
*Motor and sensory nerve endings.*--These are best stained by the
chloride of gold method (p. 82).
Specimens must be taken from the body immediately after death. The
method is therefore useless for the post-mortem room, but may be used
for tissues removed by operation. Small pieces of tissue must be
employed and must be stained in bulk, sections being made subsequently.
For motor nerve endings the muscle of a frog or human muscle from a
limb just amputated may be taken. Specimens should be prepared after
staining by teasing in preference to making sections. Mount in Farrant.
Sensory nerve endings may be conveniently studied in the cornea of a
recently killed frog or rabbit, or in a freshly extirpated human eye.
Tactile end organs may be studied in the lip or finger tips, taste buds
in the papilla foliata of the rabbit’s tongue, and Pacini’s corpuscles
are well seen in the mesentery of a thin cat.
3. *Staining nerve cells.*
*Bevan Lewis’s aniline blue-black method*:--This method is the best for
demonstrating the wealth of nerve cells in the fresh cerebral cortex.
The solution of aniline blue-black should be of the strength of 1 in
400, about a grain to the ounce. A piece of the cerebral cortex with
pia mater attached, should be removed as soon as possible after death
by parallel cuts about 1/8 inch apart, and perpendicular to the surface
of the convolution, placed on the plate of the freezing microtome and
just frozen--not too hard or the tissue will be brittle and will also
injure the edge of the razor. As soon as a good section is obtained
the razor should be plunged into a large bowl of cold water to detach
the section, which is at once floated on a glass slide, and osmic acid
solution, 1/4 per cent. allowed to flow over it from a pipette. This
will fix the tissue elements in about two minutes. The section is again
floated off into the bowl of water and thoroughly washed to free it
from the osmic acid. It is then stained either on the slide, or in a
watch-glass, with the aniline blue-black solution for an hour in the
cold, or half-an-hour if the solution is slightly warmed. The dye is
thoroughly washed away with distilled water, excess of moisture wiped
off the slide with blotting paper, and the section allowed to dry
under a glass bell jar. It is not practicable to dehydrate by means of
alcohol as it would cause sudden shrinking of the tissues. When the
section is dry a drop of Canada balsam is applied and it is covered
with alcohol in the usual way. The nerve cells and their processes are
stained a deep slate colour, as are the nuclei of the connective tissue
cells, while the ground work of the neuroglia is faintly stained and
of a neutral grey tint. This method gives beautiful results both with
normal and morbid specimens.
Various other aniline dyes, indulin, methylene blue, gentian violet,
have been employed in the same way, but none of them give such good or
uniform results as aniline blue-black.
Public-domain text, read in full here on John Shaqi.
Reviews
Reviews
No reviews yet
Be the first to share your thoughts on this work.
Join the Discussion
Join the discussion
Sign in to leave a comment or review.
Sign InorCreate an account