V#233#ronique Wunderle wrote:

> hi everybody !
> I am pretty new in the "histology world" and I am
> slowly discovering all the amazing techniques which
> are out there.
> I am starting with a basic one : H&E staining (for
> histology and counterstaining).
> I have been looking around for a protocol and as usual
> there is not one protocol but multiple variations on
> the theme !
> can anyone tell me why some people, after hematoxylin
> staining and rinsing in tap water, go straight in
> eosin whereas others bother to destain and
> differentiate in acid alcohol, wash in H2O, blue up in
> lithium carbonate or ammonia water (which one is the
> best ?)before going in eosin ?
> Time of staining in hematoxylin also varies from one
> proto to the next. Is it possible to overstain ?
> thanks.
> veronique.
>

Hi Veronique:

    To my knowledge there are two types of hematoxylin staining.
Progressive staining is done with an "acid iron chloride" type of
Hematoxylin like Weigerts. The stain is self-limiting and does not need
to be destained. The second type is Regressive staining, done with an
alum type of hematoxylin like Delafield's. After staining, the nuclear
stain is differentiated with very dilute acid to remove excess stain
from unwanted structures, then "blued" in a mild alkali (Scott's
solution for example). There are many, many variations on each type of
hematoxylin. Find one that gives results you like and stick with it.
    I also suggest an introductory textbook for your edification.
Humason's "Animal Tissue Techniques" is excellent. Kiernan's
"Histological and Histochemical Methods" is also excellent, but much
more advanced.

Geoff
--
**********************************************
Geoff McAuliffe, Ph.D.
Neuroscience and Cell Biology
Robert Wood Johnson Medical School
675 Hoes Lane, Piscataway, NJ 08854
voice: (732)-235-4583; fax: -4029
mcauliff@umdnj.edu
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