Endocrinology Flashcards
what are human endocrine diseases?
- Diabetes - up to 6% of the UK population. s
- Thyroid disorders - 5-6% of population in UK
- Polycystic ovary syndrome - 1.5% of females in the UK
- Hypogonadism- 1 in 4 men
- Osteoporosis in the over 50s - 1 in 4 women and > 1 in 8 men over the age of 50
what are the two endocrine organs?
- Primary endocrine organs whose primary function is the secretion of hormones
- Secondary endocrine organs which have a non-endocrine primary function
what are the primary endocrine organs?
- pineal gland
- hypothalmus
- pituitary gland
- thyroid gland
- parathyroid gland
- thymus
- adrenal gland
- pancreas (islet of langerhan)
- ovaries (women)
- testes (men)
what are the secondary endocrine organs?
- heart
- stomach
- liver
- kidney
- small intestine
- skin and fat
what does hypothalmus and pituitary produce?
produce many regulatory hormones which control the function of other endocrine glands
what does pineal gland produce?
produces melatonin and helps to regulate circadian rhythm –> during the day the hormones will intrinsically change.
where is the thyroid gland/
neck region just below the larynx. sitting above the trachea
what does the thyroid gland produce?
• Produces hormones T3 and T4 which help to regulate metabolism, it also produces the hormone calcitonin (involved with regulation of calcium metabolism in the body)
what does the parathyroid gland produce?
• Parathyroid gland produces parathyroid hormone (PTH) sits behind the thyroid gland, associated with the regulation of calcium, if your levels drop then you would release parathyroid hormones.
where is the thymus found?
lies close to the heart
what is the function of the thymus
- Critical for immune function because T-lymphocytes mature in the thymus part of the immune system.
- Produces he peptide hormone thymosin, which stimulates the activity of T cells & increases antibody production in bone-marrow
what is the most common thymus disease?
• The most common thymus disease is myasthenia gravis. It arises from the over-production of antibodies directed towards the nAChR at the neuromuscular junction. This causes the muscles to become weak and easily tired.
what is the function of the endocrine?
Endocrine function is to produce several important hormones: insulin, glucagon, somatostatin, ghrelin, pancreatic polypeptide. Only 1% of pancreas function is the endocrine function, the other 99% is digestion
what are the three broad groups of endocrine disorders?
- A gland does not produce enough of its hormones: hyposecretion
- A gland produces too much of its hormone, also referred to as hypersecretion
- Tumors develop in the endocrine glands. They may be malignant, or cancerous, but they may also be benign, or non-cancerous.
- Signals may be defective or the feedback mechanisms might not work which means the endocrine glands may not work properly.
what disorders are hypersecretion of endocrine glands?
- addisons disease
- hyperinsulinism
- cushings disease
- congenital adrenal hyperplasia
- graves disease
what disorders are hyposecretion?
- type 1 diabetes
- hypothryodism
- type 2 diabetes
what are disorders are caused by tumours in endocrine gland?
- multiple endocrine neoplasia
- pheochromocytoma
where are the adrenal glands situated?
top of the kidneys
what is the main responsiblity of the adrenal glands?
release hormones during stress
what are the 2 distinict regions of adrenal glands?
o Central medulla adrenaline & noradrenaline
o Outer cortex steroids e.g. cortisol
what effect does cortisol have on sterioid synthesis?
negative
what is the endocrine feedback loop?
Hypothalamus produces hormone (corticotropin) if you are stressed. This hormone then activates the anterior pituitary gland and released adrenocorticotropic hormone and activates adrenal cortex which produces cortisol.
Cortisol feedbacks and will cause negative feedback.
where are the ovaries situated?
• Female reproductive organs, located in the pelvic cavity
what do ovaries secrete?
steriods - oestrogen & progesterone, and protein hormones - inhibin & relaxin
crucial role in sexual development and reproduction
what are ovaries regulated by?
• Regulated by: Follicle stimulating hormone (FSH) & Luteinizing hormone (LH) (from anterior pituitary)
where are the testes situated?
• Male reproductive organs, located in the scrotum.
what is the primary function of the testes?
• Primary functions; sperm (spermatogenesis) and steroid hormones (androgens), primarily testosterone.
what are the steroid hormones?
- Oestrogens
* Progesterone
what are protein hormones?
- Chorionic Gonadotropin (CG)
- Corticotropin Releasing Hormone (CRH )
- Placental Lactogenic (PL)
what hormones are produced by the heart?
Atrial natriuretic peptide (ANP) stimulates kidney to secrete more salt….. thereby decreases excess blood volume; combating high BP and high blood sodium concentration
what hormones are produced by the GI tract?
largest endocrine organ, 30 hormones
what hormones are produced by the kidneys?
Juxtaglomerular cells secrete Renin. Renin indirectly signals adrenal cortex to secrete aldosterone
o Erythropoietin: signals bone marrow to increase RBC production
what hormones are produced by the skin?
Modified cholesterol with UV exposure becomes Vitamin D precursor Vitamin D necessary for calcium metabolism: signals intestine to absorb calcium
