Endocrine Patho Flashcards
Exocrine Glands
Secrete into ducts as opposed to directly into blood, excrete for elimination. Ducts carry secretions to surface. E.g sweat glands, salivary glands, liver
Endocrine glands (inside)
Secrete into blood to be carried to target tissues, they lack ducts, carry hormones
Example of endocrine glands
Pineal, ovaries/testes, pituitary, hypothalamus
What do hormones do
Increase or decrease cellular metabolism, coordinate bodily functions such as mood, growth, development, metabolism, tissue function, sexual development.
Main function to maintain homeostasis
Mixed gland
Has both endo and exo function, example is pancreas
Insulin production=endocrine
Digestive enzymes=exocrine
Double gland
Glands that secrete different hormones and have 2 different functions
Pituitary and adrenal are examples of
Where are hormones released
Directly into bloodstream, to target tissues
Cells
Many contain receptors to bind to specific hormone and initiate appropriate signal
Agonist
Molecule that binds and triggers a response by that cell that produce some kind of action
Antagonist
Bind to a cell and block that action of the agonists, widely used as drugs
Negative feedback system
Enough is enough, mechanisms work until the variable is back to original state
Positive feedback system
Give me more, mechanisms enhance the original stimulus. E.g childbirth, oxytocin
Hypothalamus
Not a gland, several control centres for body functions and emotions, primary link between endocrine system and nervous system
Some things the hypothalamus is responsible for
Releasing hormones, maintaining daily physiological cycles, appetite, sexual behaviours, emotional reponse
What is the pituitary gland
AKA master gland, its located at base of the brain behind the nose. Its secretions control or regulate secretions of so many other endocrine glands
How is the pituitary gland divided
In two regions, anterior pituitary and posterior pituitary
Anterior pituitary gland
Produces 6 hormones:
Growth hormone
Thyroid stimulating hormone (TSH)
Adreno Cortex Stimulating Hormone (ACTH)
3 Gonadotropic hormones
Mammary Gland Stim Hormones
Posterior Pituitary Gland
Secretes 2 hormones
ADH
Oxytocin
Growth hormone
regulates growth and body composition
Thyroid Stimulating Hormone (TSH)
Stimulates the thyroid to secrete its hormones
Adreno Cortex Stimulating Hormone
Stimulates the adrenal glands to secrete their hormones, principally cortisol
Gonadotropic Hormones
Act on ovaries or testes to stimulate sex hormone production, egg and sperm maturity
Mammary Gland Stim Hormone
Prolactin
ADH
Anti diuretic hormone AKA vasopressin, controls water balance and BP
Oxytocin
Stimulates uterine contractions during labour and milk secretions
Thyroid
Butterfly shaped organ, at front of neck. Primarily influences metabolic rates in the body
What 3 hormones does the Thyroid secrete
Thyroxine, Iodine, Calcitonin
Thyroxine
Major metabolic hormone, stimulates energy production in cells, increases rate cells consumes oxygen, carbs, fats, protein. Needed for normal development
Iodine
Without proper levels of this, thyroxine cannot be produced, development will be diminished
Calcitonin
Maintains normal calcium levels in blood, is secreted when HIGH levels of calcium detected, stims bone building cells to absorb calcium and kidneys to excrete it
Parathyroid
Smallest of endocrine glands, can vary in number and position. They assist in regulation of calcium and secretes parathyroid hormone (PTH)
Parathyroid Hormone (PTH)
Acts as an antagonist to calcitonin, secreted when calcium levels are LOW, causes bone dissolving cells to release calcium.
Adrenal Glands
2 asymmetrical glands on upper kidneys. Comprised of two functionally separate parts: adrenal cortex and adrenal medulla
Adrenal Cortex
Secretes Corticosteroids, 2 main mineralcorticoids (Aldosterone) , Glucocorticoids (Cortisol) and Androgens
Mineralocorticoids and Glucocorticoids
Aldosterone and cortisol, they regulate metabolism, balance of salt/water, stress, immune system, sexual function
Androgen
Male sex hormone
Adrenal Medulla
Main function of the hormones produced here is to prepare for fight or flight.
What hormones are produced in adrenal medulla
Catecholamines (Epi/Norepi) and adrenocorticotropic hormone (ACTH)
Epi/Norepi
Most of adrenaline in body. Epi causes vasoconstriction and norepi stims SNS. Stimulates liver to convert glycogen to glucose, and increase oxygen and glucose in blood
Adrenocorticotropic hormone (ACTH)
Released during stress, targets adrenal cortex and causes it to secrete cortisol, then stimulates cells to increase energy production
Pancreas
Behind abdomen, its a digestive gland, its considered endo and exo. Secretes digestive enzymes into duodenum through the pancreatic duct
Pancreas as an endocrine gland
Functions mostly to regulate blood sugar levels, secretes insulin, glucagon, somatostatin
Pancreas as part of the GI system
Secretes pancreatic juice into intestine
Islet of Langerhans
Cell groups within the pancreas, responsible for the regulation of blood glucose levels. The main hormones secreted are glucagon and insulin.
Glucagon
Produced by ALPHA cells, stimulates the liver to change glycogen into sugar when blood sugar is low
Glycogenolysis
Conversion of glycogen into glucose
Glucogenesis
conversion of nutrients into glucose, increases use fats and amino acids for energy production
Insulin
From BETA cells, enables cells to uptake glucose and allows for storage of glycogen. Secreted when blood sugar is high
Somatostatin
Produced by DELTA cells, inhibits the release of other hormones such as insulin and glucagon, therefore blood sugar rises
Gonads
Main source of sex hormones, they are follicle stimulating hormone (FSH) and Luteinizing Hormone (LH)
