Good to see you all musing on some important immunology.
Annaphylaxis can be considered as the ultimate inflammatory response that takes place when an allergen such as a bee sting or ciguatera toxin interacts with specific antibodies in our blood stream. All sorts of kinins, prostaglandins, 5HT, histamine etc are released from mast cells of our blood and in the lungs. This can cause extreme low blood pressure (hypotension) and bronchoconstriction which means that the airways become narrowed and it becomes difficult to breathe.
The use of adrenaline injection to treat this problem is a great example of physiological antagonism. Because there are so many different active substances released from mast cells as a result of the allergic reaction, its useless to use any one specific antagonist such as, say, an antihistamine. Sure, the antihistamine would stop the histamine response but it wouldn't stop any of the other responses. So, by using adrenaline, we are using a substance that raises blood pressure and dilates the airways, the two major problems with AP as related above thus effectively reversing the unwanted actions of all those mast cell degranulation products.
Just a short discourse for your edification this glorious Sunday morning.
...And bones... In my early days in the hospital wards, I may often have been referred to as "that little prick with a needle"...
