To Study Antiallergic Effect of Drug Using Mast Cell Degradation Assay | Mast cell Stabilizers

Download the "Solution Pharmacy" Mobile App to Get All Uploaded Notes, Model Question Papers, Answer Papers, Online Tests and other GPAT Materials - https://play.google.com/store/apps/de... The Mast Cell Stabilization Assay is a standard preclinical screening method used to evaluate the antiallergic and membrane–stabilizing potential of a test drug or plant extract. Mast cells are the principal effector cells of Type I (immediate) hypersensitivity reactions such as allergic rhinitis, asthma and anaphylaxis. On activation they undergo degranulation, releasing pre–formed mediators (histamine, leukotrienes, chemokines) that produce itching, swelling and bronchoconstriction. An effective antiallergic drug acts as a mast cell stabilizer, fortifying the membrane and blocking calcium influx so the cell stays intact. In this experiment, rat peritoneal mast cells are pre–treated with the standard stabilizer Disodium Cromoglycate (Cromolyn sodium, 50 mg/kg, i.p.), challenged with egg albumin, stained with toluidine blue, and the proportion of intact (granulated) versus ruptured (degranulated) cells is counted to estimate the percentage protection. Mast cells carry high–affinity IgE receptors on their surface. When an allergen cross–links membrane–bound IgE, it triggers an influx of Ca2+ ions, causing the granules to fuse with the membrane and release their contents — this is degranulation. → Sensitisation: Resting mast cell → IgE binds → sensitised mast cell. → Challenge: Antigen (egg albumin) cross–links IgE → Ca2+ influx → degranulation. → Stabilisation: Mast cell stabilizers (e.g. Disodium Cromoglycate, Ketotifen) block Ca2+ influx and stabilise the membrane, so granules are retained. Under the microscope after toluidine–blue staining: • Granulated (intact) cell – round, packed with dark blue/purple granules. • Degranulated cell – distorted, with granules burst and scattered outside the cell. The greater the proportion of intact cells in the drug–treated group, the stronger the antiallergic, mast–cell–stabilising activity of the test compound. Get in touch with the solution by just clicking the following links- Facebook Group-   / solutionpharamcy   Mobile App - https://play.google.com/store/apps/de... New Medicine Review Channel (Pharmacy Dictionary)    / @pharmacydictionary   E-Mail for official and other work - solutionpharmacy@gmail.com #solutionpharmacy #Pharmacologyclass #Pharmacology @solutionpharmacy