Hormones and Adrenal Glands Overview

Hormones

• Hormones are chemical messengers produced by endocrine glands.
• They travel through the bloodstream to target cells and tissues throughout the body, influencing numerous bodily processes, including growth, metabolism, reproduction, and response to stress.
• Different hormones have different chemical structures (steroids, peptides, or amines) and act in various ways.

Adrenal Glands

• The adrenal glands are small, paired endocrine glands located on top of the kidneys.
• They consist of two parts: the adrenal cortex and the adrenal medulla.
• The adrenal cortex produces steroid hormones, including corticosteroids (e.g., cortisol, aldosterone) and androgens (e.g., testosterone).
• Cortisol regulates metabolism, immune responses, and blood sugar levels.
• Aldosterone regulates blood pressure by influencing mineral balance.
• The adrenal medulla releases catecholamines, primarily adrenaline (epinephrine) and noradrenaline (norepinephrine), involved in the body's stress response. These hormones increase heart rate, blood pressure, and blood glucose levels.

Pituitary Gland

• The pituitary gland is a small, pea-shaped gland located at the base of the brain.
• It's often called the "master gland" because it controls the function of other endocrine glands.
• The pituitary gland has two lobes: the anterior pituitary and the posterior pituitary.
• The anterior pituitary produces and releases several hormones, including growth hormone (GH), thyroid-stimulating hormone (TSH), adrenocorticotropic hormone (ACTH), follicle-stimulating hormone (FSH), luteinizing hormone (LH), and prolactin.
• Growth hormone stimulates growth and metabolism.
• TSH stimulates the thyroid gland to produce thyroid hormones.
• ACTH stimulates the adrenal cortex to produce cortisol.
• FSH and LH regulate reproductive functions.
• Prolactin stimulates milk production.
• The posterior pituitary stores and releases hormones produced by the hypothalamus, including oxytocin and antidiuretic hormone (ADH).
• Oxytocin is involved in uterine contractions during childbirth and milk ejection.
• ADH regulates water balance by controlling kidney function.

Interconnectedness of Glands

• The endocrine system operates as a complex network, with hormones frequently interacting and influencing one another.
• The pituitary gland plays a central role in controlling the function of other endocrine glands, with hormones from one gland influencing another in a feedback loop that maintains homeostasis.