Tag: Adrenal gland

Introduction

Hormones are chemical substances that are released by ductless glands directly into the bloodstream. Although they are immediately released into the blood, only their intended target organs are affected. There are various hormones present in the body and all of them are controlled by the hypothalamus and hence it is known as the master gland. Adrenocorticotropic hormone, or ACTH, also known as corticotropin is synthesized  and secreted by the anterior pituitary gland and its targets are the adrenocortical   cells in the adrenal gland. It is responsible for the release of  glucocorticoid hormones, some sex hormones, and various other cellular pathways.

Synthesis

Synthesis of the ACTH hormone takes place in the basophilic cells of the anterior pituitary gland. It is generated from a molecule known as Pre-proopiomelanocortin or pre-POMC. This molecule signals the formation of a 241-amino-acid polypeptide POMC. This POMC undergoes various translational modifications and is ultimately cleaved by endopeptidases which yield a variety of polypeptide fragments including ACTH hormone.

Control mechanism

• The hypothalamus, the adrenal gland, and the pituitary gland are collectively known as the  hypothalamic-Pituitary-Adrenal axis and are responsible for the secretion of ACTH in the body.
• Low levels of cortisol in blood– When the level of blood cortisols are lower than normal, then the hypothalamus is triggered and it secretes corticotropin releasing hormone which in turn signals the pituitary gland to release ACTH in blood.
• High levels of cortisol in blood- The elevated levels of cortisols in the blood is detected by adrenal gland receptors. This increased level of hormone inhibits the secretion of corticotropin releasing hormone, which in turn reduces the secretion of ACTH from the pituitary gland. This process is known as the negative feedback mechanism and is responsible for maintaining the blood cortisol levels in the body.

Functions

ACTH in the body has various important functions such as-

• ACTH  stimulates  the adrenal cortex for production hormones, particularly glucocorticoids.
• It helps in the uptake of lipoproteins which in turn increases the availability of cholesterol in the adrenal cortex cells.
• It helps in the regulation of metabolism, bone reabsorption, protein catabolism, hyperglycemia and lipolysis.
• It also stimulates the secretion of other hormones for the synthesis of androgens which aids in spermatogenesis.
• ACTH release activates the  adenylyl cyclase enzyme in the cell membranes which produces cAMP, this cAMP is used in various cellular pathways.

ACTH Disorders

ACTH disorders occur due the presence of tumours near the pituitary glands, malfunctioning of the adrenal gland, congenital diseases, hypopituitarism, genetic or hereditary disorders etc.

Excess of ACTH causes- 

• Obesity in the upper body. 
• Accumulation of fat near throat region
• Stretch marks, in abdomen, thigh etc.
• Men’s diminished libido and women’s irregular menstrual cycles.

Low level of ACTH cause-

• Anorexia, or a loss of appetite.
• In the affected people, low blood sugar and potassium levels may be seen.
• Females may notice less hair growth in the pubic and armpit areas.
• Different emotional reactions such as depression and psychosis are observed.

Summary

From the above article, we learn about the synthesis of ACTH, its functions, and the diseases brought on by the body’s inappropriate amounts of this hormone. The aforementioned parts teach us about the importance of the ACTH hormone. It is a crucial hormone that triggers the release of other essential adreno-cortical steroid hormones, such as cortisol, which is in charge of the body’s metabolism and particularly the body’s reaction to stress.

Frequently Asked Questions

1. Define catabolism and anabolism.

Ans: The process of converting complex molecules into simpler ones is referred to as catabolism. Energy is eventually released from the process. On the other hand, anabolism entails the joining of smaller molecules to create a larger and more complicated molecule. Energy is required for this procedure.

2. Give the two main types of hormones found in the human body?

Ans: In general, there are two sorts of hormones.Peptide hormones -they are made of amino acids and are soluble in water. For eg-Insulin.Steroid hormones that are fat soluble are the second category. Examples include sex hormones.

3. What is produced by the medulla of the adrenal gland?

Ans: Adrenaline and noradrenaline, are the main hormones secreted by the medulla area of the adrenal gland,and which are involved in the body’s flight or fight response.

Introduction

A system of ductless glands that secrete hormones is known as an endocrine gland system. In the blood, hormones are carried directly to their target organs as chemical messengers. As hormones are synthesized in certain tissues, they trigger a cascade of events that allow for certain cellular responses. Adrenal glands are located above the kidney. They are divided into regions cortex and medulla. Both regions produce hormones that regulate electrolyte balance.

What are Adrenal Glands?

The body contains two adrenal glands. These are located above each kidney. They are a part of our endocrine system. Despite their small size, the adrenal glands are quite important for your body’s hormone-related functions. As a result, elements that affect your adrenal glands may have a big impact on your general health. If you believe you might have an adrenal problem, see a doctor.

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Location of Gland

The adrenal glands are endocrine glands that are located over the lateral surface of each kidney’s upper poles. The adrenal glands are located at the back of the abdomen, between the kidney and the ribs. They are triangular, and the parietal peritoneum only covers the front of them. The right gland is pyramid-shaped, while the left gland is moderately-lunar.

                                    

Hormones Secreted by Adrenal Gland 

• The gland’s outer layer is called the cortex. It generates both cortisol and aldosterone. The medulla is the gland’s most interior area. It generates both adrenaline and noradrenaline.
• Epinephrine, also referred to as adrenaline, is a hormone that responds swiftly to anxiety by quickening the heartbeat and raising blood sugar levels in the body. 
• Corticosterone controls the immune system and reduces inflammation in conjunction with hydrocortisone. 
• Cortisol: With the help of cortisol, the body controls and utilizes fats, protein, and carbohydrates. In addition, it weakens the immune system and affects physiology, which the body uses to help it cope with worry. 
• Aldosterone: helps the kidneys keep the blood and tissues of the body’s healthy salt chloride level. 
• Norepinephrine, also referred to as noradrenaline, works in conjunction with epinephrine to respond to anxiety. Its primary function is to prepare the body and mind for combat.

Function

• The adrenal glands are responsible for producing several hormones that help control blood pressure, produce several reproductive hormones, and maintain the proper level of salt in our blood and cells. 
• The adrenal glands’ release of stress-inducing hormones causes one of the most well-known reactions, the “conflict of the panic response.” 
• When and how rapidly an adolescent develops their reproductive system, helping during birth 
• Our endocrine system’s pituitary gland, also known as the “master gland,” controls our adrenal glands. The main controller of your endocrine glands is the pituitary gland, which is located inside your skull. Abnormal signals may interfere with the number of hormones your pituitary gland advises your adrenal glands to generate.

Disease-related to the Adrenal Gland

Adrenal gland dysfunction might manifest when 

• When your master gland is unable to efficiently regulate your hormone production, the adrenal glands may form benign or non-malignant tumours or harmful or cancerous tumours. 
• Can suffer from disorders of the adrenal glands. 
• People are born with particular gene diseases.

Cushing’s Disease

People with Cushing’s syndrome have excessive cortisol production from their adrenal glands. The most common cause of this is prolonged use of high dosages of corticosteroids. Lupus, arthritis, and pneumonia are just a few of the disorders that are treated with corticosteroids. They have cortisol-like effects throughout the body. 

Symptoms:

• The round face, the fat accumulation at the base of the neck, and the fat bulge between the arms.
• Skinny arms and thighs
• Gaining weight unnecessarily
• Prone to scarring skin
• On the hips, chest, and stomach, there are wide, violet stretch marks.

Addison Disease

A rare autoimmune ailment called Addison’s disease may develop when your adrenal glands don’t produce enough cortisol or aldosterone. This self-harm sickness may cause your immune cells to attack the tissues of your adrenal glands. 

Symptoms: 

• Arterial pressure is high despite the weight 
• Loss or gain without cause. 
• Hyperglycemia or intolerance to glucose 
• low amounts of potassium 
• Discomfort, stress, or panic episodes

Congenital Adrenal Hyperplasia (CAH)

Extremely little cortisol is synthesized in congenital adrenal hyperplasia (CAH), a genetic disease. Furthermore, persons who have this condition may also have additional hormonal issues in which their bodies create too much testosterone but not enough aldosterone.

Symptoms: 

• Early acne, body hair, beards, or loud voices (women)
• Rapid growth in children
• Sterility due to underarm hair

Adrenocortical Carcinoma

Adrenocortical carcinoma is a malignant tumour that often develops on the exterior of the adrenal gland. Oftentimes, this type of tumour is only found after it has spread to the body’s other systems over generations.

Summary

The adrenal glands are located above the kidney. Despite their small size, the adrenal glands are quite important for your body’s hormone-related functions. The gland’s outer layer is called the cortex. It generates both cortisol and aldosterone. The adrenal glands’ release of stress-inducing hormones causes one of the most well-known reactions, the “conflict of the panic response.” When your master gland is unable to efficiently regulate your hormone production, the adrenal glands may form benign or non-malignant tumours or harmful or cancerous tumours.

Frequently Asked Questions

1. Is it necessary to have both Adrenal Glands to Survive?
Ans. Since the adrenal glands are necessary for human survival, removing both of them (which is quite unusual) forces the patient to take medications and hormone replacements.

2. Is it Possible to live with just one Adrenal Gland?
Ans. Your doctor will administer painkillers to you. Your body can function regularly if your adrenal gland is working properly. If both of your adrenal glands were lost or if your remaining adrenal gland isn’t functioning properly, you might take medication every day to restore the hormones they were making.

3. Do the Adrenal Glands play a role in Digestion?
Ans. The adrenal glands release the stress hormone cortisone to inhibit bodily processes like the immune response and digestion that are not necessary for immediate survival.

4. What are Hormones that make us Drained?
Ans. The adrenal glands also create the hormone aldosterone, which is problematic since it helps regulate your body’s normal fluid and electrolyte balances. As adrenal depletion increases, it makes your body generate less aldosterone, which results in dryness and electrolyte imbalances.