Substance P is a neurotransmitter and modulates neurologic responses. It is found in many sensory nerves as well as the brain and spinal cord. It participates in inflammatory responses and is important in pain perception. It is involved in mood disorders, anxiety, stress, nerve growth, respiration, neurotoxicity, nausea, vomiting and pain perception. Its release from nerve fibers into the skin, muscle and joints is thought to cause neurogenic inflammation.
Urocortin is related to corticotropin releasing factor (CRF.) It strongly suppresses blood pressure and increases coronary blood flow. It is thought to have a role in increasing appetite during times of stress.
VEGF-A (vascular endothelial growth factor A) is a member of the platelet derived growth factor (PDGF)/VEGF family. It is important in nerve biology and is the substance mainly involved in inducing growth of blood vessels. It is heavily involved in diseases that involve blood vessels, like diabetic retinopathy and macular degeneration. It is a vasodilator and increases permeability of the smaller vessels.
VIP (vasoactive intestinal peptide) is a small protein like molecule used by nerve cells for communication. It stimulates heart contraction, vasodilation, lowers blood pressure, and relaxes the smooth muscles of the trachea, stomach and gall bladder. It also inhibits gastric acid secretion and absorption in the intestine.
Mast cell kininogenase removes a portion of a compound to release active bradykinin. This is important in the kinin system.
Phospholipase A2 promotes inflammation by initiating formation of arachidonic acid, the precursor needed to form many inflammatory molecules, including prostaglandins. Excessive levels of phospholipase A2 can lead to increased vascular inflammation, such as a seen in coronary artery disease and acute coronary syndrome. Elevated PLA2 is found in the cerebrospinal fluid of people with Alzheimer’s disease and multiple sclerosis.
Corticotropin releasing hormone (CRH) is a hormone and neurotransmitter. High CRH levels have been associated with Alzheimer’s disease and severe depression. CRH is produced in the hypothalamus and is carried to the pituitary gland, where it stimulates secretion of adrenocorticotropic hormone (ACTH.) ACTH drives synthesis of cortisol and other steroids. Imbalance of these hormones can have dire consequences.
Endothelin is the most potent vasoconstrictor currently described. It raises blood pressure and if uncontrolled, hypertension may result. It is involved in many disease processes, including cardiac hypertrophy, type II diabetes and Hirschsprung disease.
Chondroitin is found largely in connective tissues and is a principal component of cartilage. It is typically bound to other components when released from mast cells and interacts with a variety of molecules.
Hyaluronic acid is widely found in epithelial, neural and connective tissues. It participates in a variety of reactions and sees significant turnover daily. When hyaluronic acid is degraded as part of the turnover, its degradation products can cause inflammatory responses.