Final answer:
The redness caused by histamine cells or mast cells indicates an inflammation response, which involves increased blood flow due to vasodilation, swelling, warmness, pain, and often itching or other allergic symptoms. Antihistamines can reduce allergy symptoms by blocking histamine receptors, and NSAIDs can reduce pain and inflammation by inhibiting prostaglandins.
Step-by-step explanation:
Histamine cells, specifically mast cells, are responsible for the redness that signifies inflammation. When the mast cells are irritated or damaged, they release histamine, a powerful chemical that triggers vasodilation, which is the widening of blood vessels. As a result of vasodilation, there is an increased local blood flow, which brings with it warmth, redness, and swelling to the affected area - all classic signs of inflammation. In the context of an injury or infection, this inflammatory response is vital, as it increases blood flow to the affected area, bringing in phagocytes and other immune cells that help to neutralize pathogens and promote healing.
Furthermore, histamine can make the endothelium, the inner lining of blood vessels, become 'leaky', allowing white blood cells such as neutrophils and macrophages, along with fluid, to exit the bloodstream and move into the interstitial tissue spaces. This process exacerbates the swelling, known medically as edema, and contributes to the sensation of pain due to the pressure on local pain receptors. Additionally, histamine stimulates the secretion of mucus and tear formation, contributes to the itching and sneezing associated with allergies, and can relax intestinal smooth muscles leading to diarrhea.
The body's response to histamine release can be managed with various medications. For instance, antihistamines work by blocking the histamine receptors, thereby reducing the signs and symptoms of allergies. Likewise, non-steroidal anti-inflammatory drugs (NSAIDs) help in reducing inflammation and pain by inhibiting the synthesis of prostaglandins, another group of inflammatory mediators.