Alpha receptors are a type of adrenergic receptor that respond to neurotransmitters like norepinephrine and epinephrine. They are primarily involved in the regulation of various physiological processes, including blood vessel constriction, which can increase blood pressure. There are two main subtypes: alpha-1 and alpha-2 receptors, each with distinct functions in the body. Alpha-1 receptors are mainly found in smooth muscle tissues, leading to vasoconstriction when activated. In contrast, alpha-2 receptors are often located in the central nervous system and can inhibit the release of norepinephrine, resulting in a calming effect on the cardiovascular system. Together, these receptors play a crucial role in the body's response to stress and maintaining homeostasis.