Endocrinology

  • Glands and Hormones

  • Glands release hormones

  • Hormones regulate the many and varied functions of an organism

  • Hormones bind to receptors

  • Receptors are recognition sites in the various target tissues on which hormones act

  • Endocrine glands: Secrete into bloodstream

  • Thyroid gland

  • Parathyroid glands (four glands)

  • Adrenal glands (one pair)

  • Pancreas (Islets of Langerhans)

  • Pituitary gland

  • Ovaries (one pair)

  • Pineal gland

  • Exocrine glands: Send chemicals 

  • Thyroid gland

  • Parathyroid glands (four glands)

  • Adrenal glands (one pair)

  • Pancreas (Islets of Langerhans)

  • Pituitary gland

  • Ovaries (one pair)

  • Pineal gland

  • Thyroid Function

  • Secretes two hormones

    • Thyroxine or tetraiodothyronine (T4)

    • Triiodothyronine (T3)

  • Aids uptake of oxygen and regulates metabolic rate

  • Calcitonin: Tells calcium to get out of the blood and into the bone

    • Calcitonin decreases blood calcium

  • Parathyroid Glands: located dorsal of thyroid gland

  • Increases blood calcium; opposite of Calcitonin 

  • PTH (Parathyroid hormone): causes Ca to go from bones into bloodstream 

  • Adrenal gland: Hats on kidney! 

  • Makes steroids and secretes catecholamines

  • Adrenal cortex: outer portion 

    • Secretes steroids or corticosteroids

    • Secretion of SSS: sugar (metabolism of sugars), salt (regulate electrolytes), and sex (hormones)

      • Makes cortisol (increases blood glucose), aldosterone, and testosterone

      • Aldosterone balance waters and salt; tells kidney to “keep sodium”

  • Adrenal medulla: Inner portion 

    • Secretes catecholamine (neurotransmitter); there are two types

      • Epinephrine (adrenaline)

      • Norepinephrine (noradrenaline)

Pancreas

  • Location: Near and partially behind stomach

  • Insulin: decreases 👎↓ blood glucose

  • Glucagon: Increases 👍↑ blood glucose

  • NIDDM: non insulin dependent diabetes mellitus

  • IDDM: insulin dependent diabetes mellitus 

Type I: No Insulin

  • Typically occurs during adolescence 

  • Refuses to make insulin

  • Low blood sugar drops to 0 and causes organ deterioration 

Type II: Resistance to Insulin

  • Insulin is made but body is resistance

  • Reduced and cells are resistance to insulin 

    • Weight is a major factor

Hyperglycemia can lead to ketoacidosis

Hypoglycemia can lead to death


Diabetes increases risk for cardiovascular incidents! -- ↑risk of MI and CVA


TEST

  • Pituitary Gland: Located at the base of the brain.

    • Hormones: Growth hormone (GH), Thyroid-stimulating hormone (TSH), Adrenocorticotropic hormone (ACTH), Prolactin, Follicle-stimulating hormone (FSH), Luteinizing hormone (LH), Antidiuretic hormone (ADH), Oxytocin.

  • Thyroid Gland: Located in the neck.

    • Hormones: Thyroxine (T4), Triiodothyronine (T3), Calcitonin.

  • Parathyroid Glands: Four small glands located behind the thyroid gland.

    • Hormone: Parathyroid hormone (PTH).

  • Adrenal Glands: Situated atop the kidneys.

    • Hormones: Cortisol, Aldosterone, Adrenaline (epinephrine), Noradrenaline (norepinephrine), Androgens.

  • Pancreas: Located behind the stomach.

    • Hormones: Insulin, Glucagon, Somatostatin.

  • Pineal Gland: Located in the brain.

    • Hormone: Melatonin.

  • Thymus: Located in the upper chest.

    • Hormones: Thymosin, Thymopoietin.

  • Gonads (Testes in males, Ovaries in females): Located in the pelvic region.

    • Hormones: Testosterone (in males), Estrogen, Progesterone (in females).

Signs and Symptoms of Diabetes:

  • Polyuria: Frequent urination.

  • Polydipsia: Excessive thirst.

  • Polyphagia: Increased hunger.

  • Unexplained weight loss.

  • Fatigue.

  • Blurred vision.

  • Slow healing of wounds.

  • Numbness or tingling in hands and feet.

Most Accurate Test for Diabetes

  • HbA1C (Hemoglobin A1C) test measures average blood glucose levels over the past 2-3 months.

Forms of Treatments for Diabetes:

  • Lifestyle modifications: Diet, exercise.

  • Oral medications: For Type 2 diabetes.

  • Insulin therapy: For Type 1 and some cases of Type 2 diabetes.

Type I vs. Type II Diabetes:

  • Type I: Autoimmune condition where the body's immune system attacks insulin-producing beta cells in the pancreas.

  • Type II: Characterized by insulin resistance, where cells fail to respond to insulin properly, often due to lifestyle factors.

NIDDM and IDDM:

  • NIDDM: Non-Insulin Dependent Diabetes Mellitus, mostly referring to Type II diabetes.

  • IDDM: Insulin-Dependent Diabetes Mellitus, mostly referring to Type I diabetes.

Hypoparathyroidism:

  • Hallmark sign: Tetany (involuntary twitching) due to hypocalcemia (low blood calcium levels).

Hyperparathyroidism:

  • Abdominal pain, high calcium in your bones, excess parathyroid hormone, kidney stones which makes you groan, and bone pain

Hypothyroidism:

  • Signs: Fatigue, weight gain, cold intolerance, constipation, dry skin, hair loss, depression.

Hyperthyroidism:

  • Signs: Weight loss, rapid heartbeat (tachycardia), heat intolerance, sweating, tremor, nervousness, irritability.

Blood Test Results:

  • Hypothyroidism: Low T3 and T4, high TSH.

  • Hyperthyroidism: High T3 and T4, low TSH.

Glands involved in Cushing's Disease and Addison's Disease:

  • Cushing's Disease: Often involves the pituitary gland (due to excessive production of ACTH), sometimes the adrenal glands.

  • Addison's Disease: Involves the adrenal glands (due to insufficient cortisol production).

Tests for Diagnosis:

  • Cushing's Disease and Addison's Disease: ACTH stimulation test to measure cortisol response. High ACTH and low cortisol indicate Addison's, while low ACTH and high cortisol indicate Cushing's.

What gland makes melatonin

  • Pineal

Three P’s for Diabetes: Polyphagia, Polyuria, Polydipsia