Endocrine System and Kidney Function

Posted on Feb 11, 2025 in Biology

Endocrine System

Pancreas

Located in the upper abdomen, the pancreas secretes hormones:

  • Insulin: Regulates blood glucose levels.
  • Glucagon: Increases blood glucose concentration; its action opposes insulin.

Pituitary Gland

Located below the hypothalamus, the pituitary gland secretes hormones such as:

  • TSH (Thyroid Stimulating Hormone): Stimulates the thyroid.
  • Antidiuretic Hormone (ADH): Acts on the kidneys.
  • Oxytocin: Stimulates contraction of the myometrium (uterine muscle).

Thyroid Gland

Located in the anterior neck, the thyroid gland secretes hormones with key effects on the body, such as thyroxine (T4).

Parathyroid Glands

Four small glands located on the back of the thyroid, the parathyroid glands synthesize parathyroid hormone (PTH), which is related to calcium and phosphorus metabolism.

Adrenal Glands

Located at the top of the kidneys, the adrenal glands secrete the hormones epinephrine (adrenaline) and norepinephrine (noradrenaline).

Neurological Conditions

Alzheimer’s Disease

A genetic disorder caused by the destruction and disappearance of neurons in the cerebral cortex, triggering progressive and irreversible dementia.

Parkinson’s Disease

A chronic and progressive neurodegenerative disease of the nervous system, causing impaired mobility due to decreased dopamine production (a neurotransmitter involved in controlling movement speed and precision).

Diabetes Mellitus

A metabolic disease caused by a decrease in all or part of insulin secretion.

Epilepsy

A condition characterized by loss of consciousness, often accompanied by convulsions.

  • Grand Mal: Characterized by generalized convulsions preceded by an aura.
  • Petit Mal (Absence Seizure): Features loss of consciousness without convulsions.

Kidney Function

Filtration

Occurs in the glomerulus; it is the elimination of waste products from the blood through urine.

Reabsorption

The transport of essential substances and water from the tubular lumen back into the blood.

Secretion

The movement of solutes and water from the blood into the tubular lumen.

Antidiuretic Hormone (ADH)

Regulates water absorption and elimination based on the body’s needs.

Aldosterone

A steroid hormone. When blood pressure decreases, the adrenal gland increases aldosterone secretion. This causes the kidneys to retain salt, which stimulates water retention, increasing blood volume and raising blood pressure.

Renin-Angiotensin System

A hormone system that elevates blood pressure when it drops. The kidneys release renin, which stimulates angiotensin.

Endocrine Functions of the Kidney

The kidney contributes to hormonal balance by:

  • Producing hormones: renin, angiotensin, erythropoietin, prostaglandins.
  • Activating vitamin D, which is involved in calcium metabolism.

Water Volume Regulation

Fluid loss is compensated by:

  • The thirst mechanism (fluid intake).
  • Kidney function and antidiuretic hormone (ADH).

Fluid Balance

Intake

  • Water intake (thirst mechanism).
  • Endogenous water (from metabolic processes).
  • Other: gastrointestinal intubations, intravenous fluids, blood administration.

Loss

  • Diuresis (urine).
  • Sweat.
  • Stool.
  • Insensible losses (breathing, skin).
  • Other: vomiting, gastric suction, drains, bleeding.