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Mast Cell stabilizers When it comes in contact with the allergen, if the sensitive mast cell could be prevented from rupturing, it would not spill out the chemical mediators and the entire cascade of events that trigger all allergic reactions would not happen. How the mast cell ruptures There are two triggers on the membrane that result in mast cell rupture:
After the trigger, the response is the same for both. When the cell membrane is breached by IgE or cholinergic stimulation so that Ca ++ can move into the cell, the storage vesicles called ‘granules’ which hold the chemicals are shoved against the membrane until they burst open. A destabilized mast cell looks a lot like a balloon over-filled with ball bearings. The ball bearings push against the plastic and with only a little shove could burst though and rip the balloon. A stabilized mast cell’s surface looks like the balloon with some of the ball bearings removed so that there is less pressure on the plastic. Mast cell stabilizers are a class of drugs that prevents the influx of calcium so that the granules don’t get shoved so hard against the membrane that they rupture. Mast cell stabilizers will not have any affect on the chemical mediators once they are released--- so these drugs are preventative only. A second method describing how mast cell stabilizers might work It has been suggested that these drugs might interfere with mast cell degranulation by the inhibition of chloride ion transfer into the mast cell. These drugs also seem to hamper chloride ion transfer into epithelial cells [capillary walls] and muscle cells. This blockage of chloride transfer & inhibition of sensory neurons might cause the muscle to be less ‘twitchy’ and irritable. Specific mast cell stabilizers
Anti-leukotrienes/Leukotriene Modifiers The Leukotrienes are the first new class of anti-asthmatic drug in 20 years. When a person has an allergic reaction, the reaction can start immediately then subside with time or drugs, but 6 hours later the reaction is more profound and the bronchospasm worse and harder to reverse. T rupture of the mast cell’s membrane releases arachidonic acids. Arachidonic acids start a reaction that forms leukotrienes. It is the leukotrienes that are responsible for this slow-acting, much stronger second phase of the allergic reaction. The leukotrienes cause bronchospasm, vasodilation, increased vascular permeability, and increased mucus secretions, as well as decreased mucociliary clearance. There are two types of anti-leukotrienes: [1] one that inhibits the synthesis of arachidonic acids into leukotrienes and [2] the two drugs that are leukotriene antagonists that block the leukotrienes receptors. (zafirlukast & montelukast.]
Specific anti-leukotrienes IgE Blocker
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