Difference Between Alpha and Beta Receptors (With Table)

The human body is designed to withstand stress and respond to it. The flight or fight mechanism is a response to the stress in our body. Alpha and Beta Receptors are the two types of adrenergic receptors involved in the modulation of the fight-flight mechanism in our body.

Alpha Receptors vs Beta Receptors

The main difference between Alpha Receptors and Beta Receptors is that Alpha Receptors vitalize the effector cells. On the other hand, Beta receptors control the effector cells.

Alpha receptors are also known as adrenergic receptors, which are a class of G protein-coupled receptors, which are considered to give a quick response to a body’s neurotransmitter, I.e norepinephrine, and epinephrine. Receptors are located at the postsynaptic area of our body’s sympathetic neuroeffector junctions. They have two main receptors, I.e Alpha 1 and Alpha 2 receptors.

Beta receptors are also called adrenergic receptors located postsynaptically at our organs, particularly under smooth involuntary muscles, which include organs like the heart, uterus, blood vessels, and fatty tissues. Beta receptors control the effector cells. There are mainly 3 subdivisions of Beta Receptors.

Comparison Table Between Alpha Receptors and Beta Receptors

Parameters Of ComparisonAlpha ReceptorsBeta Receptors
DefinitionAlpha Receptors come from a class of G protein receptors that help in controlling vasoconstriction, intestinal relaxation, and other psychological processes.Beta Receptors are adrenergic receptors it helps in controlling increased blood pressure, heart rate, and bronchial relaxation.
ActivityAlpha Receptors rejuvenate effector cells.Beta Receptors control the effector cells.
FunctionAlpha Receptors are responsible for blood vessel contraction in our body.Beta Receptors are involved in the dilation of blood vessels.
LocationAlpha Receptors are located beneath the smooth muscle and effector tissue.Beta Receptors are located beneath the uterine muscle and cardiac muscle.
TypeAlpha Receptors are further divided as Alpha I and Alpha II receptors.Beta Receptors are subdivided into Beta I, Beta II, and Beta III Receptors.

What is Alpha Receptors?

Alpha receptors are the adrenergic receptors that come from class G protein-coupled receptors, which are quickly responsive to a body’s neurotransmitter and help in controlling vasoconstriction, intestinal relaxation, and other physiologic processes.

Receptors are located at the postsynaptic area of our body’s sympathetic neuroeffector junctions. Alpha receptors are further subdivided into Alpha I and alpha II receptors.

Alpha receptors play a very important role in our body, Alpha receptors vitalize the effector cells, contract vessels of our skin, and skeletal muscles. Besides that, Alpha receptor cells are responsible for blood vessel contraction and help in controlling blood pressure levels in our body.

Alpha receptors are also responsible for gluconeogenesis and glycogenesis in our bodies. Correspondingly, it also controls any options of the gastrointestinal system. It also helps in synchronizing uterine contraction in pregnant women.

Alpha receptors are further subdivided into Alpha I receptors and alpha II receptors. Alpha 1 receptors are subdivided into two additional units. Which are Alpha 1 agonists and Alpha 1 Blockers. Alpha 1 receptors are used in the treatment of heart failure, shock, decompensation also for cardiopulmonary resuscitation.

Alpha 2 receptors are used for treating post-traumatic stress disorders. Alpha 2 receptors in the brain stem control the sympathetic activity and help in controlling blood pressure, it comprises the clonidine and guanfacine that are used as antihypertensives. Alpha 2 receptors are divided into two types and are called Alpha 2 agonists and Alpha 2 blockers.

What is Beta Receptors?

Beta receptors are also known as adrenergic receptors located at the surface of cells. Particularly, It is located in smooth involuntary muscles, including the heart, uterus, blood vessels, and adipose tissue.

The Beta-receptor helps in controlling effector cells and is involved in the dilation of blood vessels and also helps in maintaining heart rate, blood pressure, and bronchial relaxation.

Beta Receptors are further divided into three units.

  1. Beta 1, Receptors: Beta 1 Receptors are detected in the heart. When Beta 1 Receptors are revitalized, it increases the heart rate and also increases the strength of heart contraction.
  2. Beta 2, Receptors: Beta 2 Receptors cells are located in the bronchioles of the lungs and also in the arteries of the skeletal muscles. It helps in managing bronchospasm in patients with asthma and also for chronic obstructive pulmonary diseases.
  3. Beta 3, Receptors: Beta 3 Receptors are seen in the urinary bladder, gallbladder, and also on the surfaces of both white and brown adipocytes, and help in the relaxation of intestinal smooth muscles and also in the thermogenesis process.

Main Differences Between Alpha Receptors and Beta Receptors

  1. Alpha Receptors come from a class of G protein receptors that help in controlling vasoconstriction, intestinal relaxation, and other psychological processes. Whereas, Beta Receptors are adrenergic receptors that help in controlling increased blood pressure, heart rate, and bronchial relaxation.
  2. Alpha Receptors are located beneath the smooth muscle and effector tissue where Beta Receptors are located beneath the uterine muscle and cardiac muscle.
  3. Alpha Receptors rejuvenate effector cells. On the other hand, Beta Receptors control the effector cells.
  4. Alpha Receptors are responsible for blood vessel contraction in our body. Whereas, Beta Receptors are involved in the dilation of blood vessels.
  5. Alpha Receptors are further divided as Alpha I and Alpha II receptors however Beta Receptors are subdivided into Beta I, Beta II, and Beta III Receptors.

Conclusion

Alpha and Beta Receptors are adrenergic receptors that help in the modulation of the fight-flight mechanism in our body. Both differ in various aspects, such as the function, type, and effect of the receptor on effector cells.

Alpha and Beta receptors help maintain stress in the body as well as intestinal relaxation, heart rate, and also help maintain a healthy body.

References

  1. https://www.sciencedirect.com/science/article/pii/0002914986907162
  2. https://europepmc.org/article/med/7920178