A receptors
A receptors are specialized cellular receptors in the body that are responsible for transmitting signals between cells and regulating their functions. They are a collection of protein structures located on the surface of cells and act as bridges connecting chemicals to specific receptor sites in the cell membrane.
A - receptors are one of the most numerous types of receptors - there are many types, each of which binds a specific molecule or ion and takes part in the regulation of physiological processes. a - receptors constitute a separate subtype of receptors that form a group of agonist receptors. Of more than 20 types of receptors of this type, 7 have been reliably characterized to date, and less is known about the action of 4 of them, because they were introduced artificially: h2-histamine receptor; 2a-adrenergic receptor; sepetidine 2b receptor.
**Functions** A – Receptors:
1. Regulation of cell function by transmitting signals with a plus sign. For example, the hormones adrenaline or norepinephrine bind to group a1 receptors and have an antihypertensive effect (lowering blood pressure). At the same time, cyclic AMP accumulates inside the cytosol and activates several signaling pathways. a1 receptors are widespread throughout the body of animals, but these receptors are absent in the brain. At the same time, in humans, both types of receptors are present in most tissues. 2. Features of cellular metabolism. They are only affected by adrenaline and norepinephrine. These are predominantly white bodies located on the inner lining of the arteries. 3. Formation and release of central cytokines from presynaptic vesicles, which provide immediate