Are you aware that there are many types of cancer your canine or feline companion can develop?
On the Honest Kitchen Blog I’ve covered Lymphoma, a type of white blood cell cancer see article here. Another common and potentially deadly type of cancer are Mast Cell Tumors.
What are Mast Cells?
Mast cells (AKA mastocytes) are white blood cells involved in the process of regulating a variety of bodily functions. White blood cells are immune system cells having responsibility to control inflammation, fight infection, clean up the breakdown products of day-to-day cellular function, and more. The liver, spleen, bone marrow, and lymph nodes are organs where white blood cells are produced and stored. Besides being in tissues, most white blood cells circulate throughout the body in the lymphatic system and blood vessels.
Mast cells are some of the body’s first-line defenders and are mainly found imbedded in tissues and organs. Unlike other white blood cells, mast cells don’t circulate throughout the body in the blood. Mast pacells primarily help protect the body from parasites, but in actuality the world in which our domesticated pets live is relatively parasite-free.
Mast cells are filled with granules, which are sack-like pockets of biochemicals that help protect the body from invading pathogens (parasites, etc.) and antigens (immune system stimulating substances, like pollen, etc.). Instead of their primary role protecting the body from the effects of parasites, mast cells are stimulated to release their granules after encountering common substances in our environment, like pollen, which leads to an allergic response.
When mast cells release their granules, a variety of physiologic changes take place. This process is called degranulation and can be a normal response to environmental allergens or as an allergic response to a chemical stimulant (bee/insect venom, etc.). This can lead to mild to severe clinical signs of lethargy, nasal cavity secretions, appetite changes, decreased mobility, and more.
The biochemicals released from mast cell granules include:
Bradykinin —A peptide (protein) that causes blood vessels to dilate, which in turn can cause runny eyes and nose, reduced blood pressure, and smooth muscle constriction.
Heparin—A complex of peptide (protein) bound to a complex sugar (polysaccharide), which delays blood clotting times by preventing platelets from aggregating to form a clot.
Histamine —A nitrogen-based biochemical which makes blood vessels more permeable to the movements of white blood cells in order for the white blood cells to do their job in defending against invading bacteria, parasites, and viruses. Histamine release also promotes stomach acid production. When histamine is released it can cause the sensation of itching, which is why antihistamines are commonly used when controlling allergies in pets and people.