P/hii/ary and Pancreas 283 



results: 



mast cell granules — reddish purple 



background — faintly blue 



cartilage — reddish purple (will be the only other tissue staining meta- 



chromatically) 



comments: 



The toluidine blue in many methods reverts to its orthochromatic 

 (blue) color during dehydration; therefore it is the usual practice to 

 prepare an aqueous or glycerine mount to produce only semi-perma- 

 nent results. Padawer suggests that partial hydration is required for 

 metachromasia and ether 181 does not completely hydrate the tissue, 

 A specific concentration is used in which both mast cell polysac- 

 charides and toluidine blue are poorly soluble. 



Belanger and Hartnett {I960) use the following solution: 



potassium acid phthalate-tartaric acid 1.0 gm. 



distilled water ; 100.0 ml. 



toluidine blue O, C.I. 52040 0.5 gm. 



The dye requires 24 hours to dissolve. Filter before use. Good for one 

 week. 



procedure: Stain for 10 minutes; rinse in fresh phthalate-tartaric acid 

 buffer (I gm./lOO ml. water): 2 minutes; dehydrate in tertiary butyl 

 alcohol, 4 changes: 2 minutes each; clear and mount. 



Pituitary and Pancreas 



The staining of the cytoplasm and its elements is used to characterize 

 and differentiate the cells of the anterior pituitary. The orlandular 

 cells are classed as either chromophils or chromophobes. Seventy-five 

 per cent of the chromophils are normally acidophilic (acidophils, some- 

 times called alpha cells) and twenty-five per cent are basophilic (baso- 

 phils). The latter group is made up of gonadotrophs [delta cells) and 

 thyrotrophs (beta cells). Every few months a new method seems to 

 appear in the literature, suggesting that the ideal procedure is being 

 elusive. Certain reactions seem to be specific for certain cells. Thyro- 

 trophs and gonadotrophs have an affinity for Schiff's reagent, thyro- 

 trophs also stain with Gomori's aldehyde fuchsin or aldehyde thionin. 

 Acidophil granules differentiate sharply in Eljtman's {I960) method. 

 Orange G also stains them. Paget and Eccleston {1959, 1960) use luxol 

 fast blue to distinguish them. 



