Inflammation 1 the horrible hidden hormones
These substances are not made by distinct, specialised glands, but by a variety of cells (see inflammation 2). The great majority of their actions are on site. In some cases they circulate in the blood to exert hormonal effects on distant organs and tissues involved on our defences, and also on the guerrilla army of cells that have moved from the blood into places like the brain, gut, heart and placenta to lie in wait for infection and ambush any viruses or bacteria.
a) cytokines (over a hundred), the interleukins
b) chemotaxins
c) kinins
d) Complement
e) Products of blood clotting
f) Histamine
g) Eicosanoids
h) Lysosomal enzymes and nitric oxide
You get the picture, you probably haven’t heard of many of these…but I haven’t made them up. A completely up to date textbook would list more, show up more connections, describe a bigger circulation.
If ordinary hormones are the long range parcel service, then cytokines start out as notes from next door neighbours, except that they are a windswept snowstorm of paper, of many colours.
They were the killers in Spanish Flu, and create the final stage of lethal Bird Flu. We need them to fight viruses and bacteria, and heal cuts and stings, but when they are switched on by the wrong things, or get too active, they get too damaging.
When the amounts are too high they stop being local (microscopic distances) and go global. They hang around for many hours, some for days others for weeks. They leave the lungs ready to react faster and more intensely to the next lot of pollution. This makes such biological nonsense of the common number averages used in counting pollution. Their switch is on/off, and gets more sensitive as the day goes on *see the nox/ozone graphs of lethal London levels.
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