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					General histological stain                                                                     PAS                                                                CIG/PHENOTYPAGE



                                                              PERIODIC ACID SCHIFFS
Purpose: Structures rich in polysaccharides, mucopolysaccharides, or glycolipids are the principal tissues stained with Schiff's reagent. This
method is used for detection of glycogen in tissues such as liver, cardiac and skeletal muscle; for demonstration of mucosubstances secreted
from the epithelia of various organs (Intestin = goblett cells, paneth cells; mucous gland), fungi , and adenocarcinoma from undifferentiated
squamous cell carcinoma. A routine stain for liver and kidney biopsies.



Principale: The PAS stain is a histochemical reaction in that the periodic acid oxidizes the carbon to carbon bond forming aldehydes which
react to the fuchsin-sulfurous acid which form the magenta color.



Tissus control:                  use skin, aorta, intestine or normal liver for positive PAS staining. For staining fungus a known fungus control
                                 must be used
Fixative:                        PFA 4%, Formaline 10% or any well fixed tissue

Sections:                         paraffin sections or cryo sections



  METHOD                                                                                  Time                                             Results

                 Dewax and hydrated to water

                 treat with 1% periodic acid                                             10 min

                 Wash well in water

                 Treat with Schiffs reagent                                              15 min                          Magenta                     Mucins, glycogen, fungi
                                                                                                                                                     periodate carbohydrate
                 Wash well in running tap water

                 Stain in alun hematoxylin                                                5 min                             Blue                     Nuclei

                 Differenciate in acid alcohol                                       few seconds

                 Wash well and let "Blue" in tap water                                   10 min

                 Dehydrated, clear and mount sections in Eukitt

            NB: Do not over stain in Schiffs reagent - it is irreversible. Wash for several mins at step 5 to bring out the colour
                of the Schiffs.It may be combined with a light green counterstain after step 8, by placing slide 2 min in LG working solution
                as used for TG, then rinsing briefly in water and continuing step 9




Rédigé par C.ROGER                                                                           page 1                                                                    date: 5.01.2007
General histological stain                 PAS              CIG/PHENOTYPAGE



                                      Intestine

Pictures




                             Mucins                Nuclei




Rédigé par C.ROGER                        page 1                date: 5.01.2007

				
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