International Journal of Health Sciences & Research (www.ijhsr.org) 66 Vol.3; Issue: 2; February 2013 International Journal of Health Sciences and Research www.ijhsr.org ISSN: 2249-9571 Original Research Article A Newly Identified Stain for Mast Cells in Human Mesentery Roopa Ravindranath, R.Victor, Amith Ramos * , V. Sumitra Histology Laboratory, Dept. of Anatomy, St. John’s Medical College, Bangalore-560034. * Correspondence Email: amith_ramos@hotmail.com Received: 03/01//2013 Revised: 31/01/2013 Accepted: 04/02/2013 ABSTRACT For invitro studies in mesentery toluidine blue and thioninare generally used. We have identified a new stain and found it to be good as it showed good contrast between Mast cells and the background tissue. A simple, cost effective and rapid method for staining mast cells in human mesentery is described. Mesentery was removed from embalmed cadaver and cut into pieces, spread on glass slides, tied with the thread on both sides and fixed in 10% formalin overnight and stored in 70% alcohol. Small pieces of convenient size were cut and transferred into a petri dish, washed thoroughly and was spread on a glass slide. The tissue was stained with Methyl Violet 10B (MV10B) stain for 1 minute, washed, dehydrated, cleared and mounted in DPX. Mast cells were seen against light connective tissue background. Key words: Stain, Mast Cells, Human Mesentery INTRODUCTION Mast cell function has been attributed to wound healing, immune allergic reaction and regeneration among other functions. They are widely distributed in the connective tissue. The abundant granules stain metachromatically with thiazide dies such as toluidine blue. They also stain with copper phthalocyanine dyes such as alcian blue and astra blue. [1] Astra blue has been used to stain differentially mast cells in the intestine. However the procedure has not been widely used because of difficulty in preparing and using the dye solution. [2] In the present study the contrast between the deeply stained granules and the lightly stained background facilitates detection and counting of mast cells. This can be used to advantage for routine study of mast cells. MATERIALS AND METHODS Mesentery was removed from embalmed cadaver during the routine dissection of the abdomen. The sheet of mesentery was cut into small pieces to accommodate in the slides. The cut pieces were spread on a slide and tied with thread from both sides. The slides were fixed in 10 % formalin overnight and storedin 70% alcohol. Small pieces were cut, transferred into a petri dish and were washed thoroughly. The bits were taken on to the slides and stained with MV10 stain for 1 minute, washed, dehydrated cleared and mounted in DPX.