Difference Between Adrenergic and Cholinergic (With Table)

The adrenergic and cholinergic receptors are vital for binding the neurotransmitters. Sympathetic and parasympathetic nervous systems together make the autonomic nervous systems. Humans do many actions or acts without conscious recognition or any efforts given by human beings.

The autonomic nervous system controls these actions. These receptors are known for different functions in the human body. The role of adrenergic receptors is to help the human body show better performance.

On the other side, the cholinergic receptors would be responsible for countering the functions of the adrenergic receptors. These reports are pivotal for balancing and managing each other’s functions for making the human body’s nervous system work well.

Adrenergic vs Cholinergic

The main difference between the adrenergic and cholinergic is that both these receptors use different neurotransmitters present inside the human body. The adrenergic would bind with the neurotransmitters, while the cholinergic receptors would bind to the acetylcholine neurotransmitters.

The adrenoceptors are mainly present in the body for showing the acute stress response. In intense or stressful situations, the adrenergic receptors would work to show their effectiveness against any acts or actions that need a fight or flight response.

To balance out the functions of adrenoceptors, another receptor is found in the human body known as a cholinergic receptor. The presence of cholinergic receptors is linked with the PNS (parasympathetic nervous system). The human digestive tract works efficiently due to the presence of cholinergic receptors.

Comparison Table Between Adrenergic and Cholinergic

What is Adrenergic?

Adrenergic refers to the physiological and pharmacological effects of activating the sympathetic nervous system, which is a part of the autonomic nervous system. The term “adrenergic” is derived from “adrenaline” or “epinephrine,” which are two closely related hormones and neurotransmitters that play a central role in the sympathetic response.

Key points about adrenergic function include:

1. Sympathetic Nervous System: Adrenergic effects are primarily mediated by the sympathetic nervous system, called the “fight or flight” system. The sympathetic system is activated when the body perceives a threat or requires increased energy and alertness.
2. Neurotransmitters: Adrenergic responses are triggered by neurotransmitters, including norepinephrine (noradrenaline) and epinephrine (adrenaline), released from nerve endings and the adrenal glands in response to stress or stimulation.
3. Physiological Effects: Adrenergic activation leads to a range of physiological responses, including increased heart rate, increased blood pressure, dilation of airways, increased alertness, and mobilization of energy reserves. These responses prepare the body to respond to a perceived threat or challenge.
4. Clinical Relevance: Various medications target adrenergic receptors, including adrenergic agonists (stimulants) and antagonists (blockers). These drugs treat conditions like asthma, hypertension, and cardiac arrhythmias by modulating adrenergic responses.
5. Adrenergic Receptors: Adrenergic responses are mediated through adrenergic receptors, including alpha and beta. Different tissues and organs have varying combinations of these receptors, leading to diverse effects in different body parts.

In summary, adrenergic refers to the body’s responses to the activation of the sympathetic nervous system, leading to physiological changes aimed at increasing alertness and energy in response to stress or challenges. Understanding adrenergic mechanisms is crucial in physiological and clinical contexts, as it plays a central role in the body’s response to various stimuli.

What is Cholinergic?

Cholinergic refers to the physiological and pharmacological effects of activating the parasympathetic nervous system, which is a part of the autonomic nervous system. The term “cholinergic” is derived from “choline,” a precursor of acetylcholine, a key neurotransmitter in this system. Cholinergic responses are essentially the opposite of adrenergic responses, which are mediated by the sympathetic nervous system.

Key points about cholinergic function include:

1. Parasympathetic Nervous System: Cholinergic effects are primarily mediated by the parasympathetic nervous system, called the “rest and digest” system. This system is active during periods of relaxation and recovery.
2. Neurotransmitter Acetylcholine: Cholinergic responses are triggered by acetylcholine, a neurotransmitter released by cholinergic nerve endings. Acetylcholine is central in transmitting signals between nerve cells, nerves, and muscles.
3. Physiological Effects: Cholinergic activation leads to a range of physiological responses, including decreased heart rate, decreased blood pressure, increased digestive activity, constriction of airways, and relaxation of smooth muscles. These responses promote relaxation and the conservation of energy.
4. Clinical Relevance: Cholinergic receptors are targeted by various medications, including cholinergic agonists (stimulants) and antagonists (blockers). These drugs treat glaucoma, myasthenia gravis, and gastrointestinal disorders by modulating cholinergic responses.
5. Cholinergic Receptors: Cholinergic responses are mediated through cholinergic receptors, including muscarinic and nicotinic receptors. Different tissues and organs have varying combinations of these receptors, leading to diverse effects in different body parts.

In summary, cholinergic refers to the body’s responses to activating the parasympathetic nervous system, leading to physiological changes aimed at relaxation and energy conservation. Understanding cholinergic mechanisms is crucial in physiological and clinical contexts, as it plays a central role in the body’s response to various stimuli, especially during rest and recovery.

Main Differences Between Adrenergic and Cholinergic

Conclusion

Adrenergic and cholinergic receptors are important components or parts of the autonomic nervous system. The working functions of the receptors depend on the binding of the neurotransmitter.

Both of these receptors are linked to different divisions of the nervous system. The adrenergic receptor is vital to the sympathetic nervous system, while the cholinergic receptors work for the parasympathetic nervous system.

The adrenergic receptors are responsible for increasing the person’s heart rate, while the cholinergic receptors can reduce or down-regulate the heart rates.

The adrenergic receptors are responsible for increasing people’s blood pressure, whereas the cholinergic receptors have no function in increasing the blood sugar level.

The adrenergic receptors would increase glucose availability by providing blood to the skeletal muscles. The adrenergic receptors are responsible for dilating the pupils, whereas the cholinergic receptors are responsible for dilating the blood vessels.

The adrenergic receptors are classified into alpha and beta receptors, which have further classification. The cholinergic receptors are classified into muscarinic and nicotinic receptors with no further classification.

The adrenergic and cholinergic receptors trigger the nerve impulse, but both work differently.

References

1. https://www.ahajournals.org/doi/abs/10.1161/01.CIR.101.5.558
2. https://www.sciencedirect.com/science/article/pii/S0021925818541557