Endorcine system Flashcards
What are the 3 main types of hormones
lipid-derived, amino acid-derived, and peptide.
What is hormone secretion stimulated by
-Other hormones (stimulating- or releasing -hormones)
-Plasma concentrations of ions or nutrients, proteins
-Neurons and mental activity
-Environmental changes (light or temperature)
Explain autocrine, paracrine and endocrine
Autocrine:cell products act on itself
Paracrine:localized action around production site (short distance)
Endocrine: products secreted into blood stream to have action at distant sites (long distance)
Hormones are commonly regulated in response to what?
response to level of hormone in circulation (pituitary hormones), or in response levels of substances in the blood (glucose)
What hormones are produced by the anterior lobe of the pituitary gland and what are their functions?
Growth Hormone (GH) stimulates tissue growth, Prolactin promotes milk production, TSH stimulates thyroid hormone release, ACTH triggers adrenal hormone release, and FSH/LH regulate sexual development and fertility.
What hormones does the posterior lobe of the pituitary gland secrete, and what do they do?
Antidiuretic hormone (ADH) makes urine more concentrated by increasing water reabsorption, and Oxytocin stimulates uterine contractions and milk secretion.
What are tropic hormones
hormones that stimulate other endocrine glands to release their hormones. You can imagine tropic hormones as “messengers” that go to a specific target (endocrine glands) and tell them to do their job, like a coach giving instructions to players on a team. These hormones don’t directly cause effects themselves but regulate other glands to release their hormones, keeping the body in balance.
Explain Panhypopituitarism
condition where the ANTERIOR pituitary gland fails to secrete any of its hormones
Explain Effects of Anterior Lobe Failure
When the anterior lobe isn’t functioning properly, it can lead to conditions like pituitary dwarfism, where there is a deficiency in growth hormone. This causes stunted growth and development, but can be treated by supplementing with growth hormone (GH).
Explain Effects of Posterior Lobe Failure:
If the posterior lobe isn’t secreting antidiuretic hormone (ADH), it can result in diabetes insipidus, where the kidneys are unable to reabsorb water, leading to the excretion of large amounts of diluted urine. This can be managed by supplementing with ADH and ensuring increased fluid intake.
What does the effectiveness of hormone action depend on
how well the receptors or target tissues function. For example, in androgen insensitivity syndrome, the body is unable to respond to androgens (male sex hormones), even though they are present.
Explain Functional tumors:
These tumors produce hormones that can lead to symptoms like excessive growth or changes in milk production, depending on which hormone is affected. The majority of these tumors are adenomas, which are benign but can still cause serious issues because they disrupt normal hormone production and may press on nearby structures, like the optic chiasm, affecting vision.
explain Nonfunctional tumors
These tumors don’t produce hormones but still cause problems by pressing on surrounding tissues and structures, leading to symptoms like headaches or vision issues due to their size and location.
Growth hormone overproduction occurs due to?
pituitary adenoma -benging
hypertrophy-enlargment of pituitary.
What is acromegaly
The bones thicken and enlarge
Prolactin overproduction results from?
too much prolactin in the body, often due to adenoma
In women what can high prolactin (hyperpolactinemia) levels cause
galactorrhea and It can also inhibit FSH/LH, hormones needed for ovulation, leading to anovulation (lack of ovulation) and amenorrhea (no menstrual periods).
In Men what can high prolactin levels (hyperpolactinemia) cause
infertility (FSH - spermatogenesis), hypogonadism, sexual dysfunction
(LH - testosterone)
WHAT is the treatment for hyperpolactinemia
dopamine agonists
what is Thyroglobulin
protein produced by the thyroid gland that helps the body produce and store hormones and iodine
What kind of hormones does the thyroid produce and explain how they are made + what they do
T3 and T4 made using iodine.
They control the rate at which the body burns calories and uses energy, Growth, amongst other things i dont need to know for the exam.
What can cause hyperthyroidism.
-Adenoma
-Graves disease: immune system mistakenly attacks thyroid. Normally, the thyroid is controlled by TSH, but in Graves’ disease, the body makes an antibody called TSI.
TSI acts like TSH and tells the thyroid to make too much thyroid hormone.
The thyroid keeps making more hormones, even though the body doesn’t need it, because TSI doesn’t listen to the normal control systems.
What is Myxedema
condition caused by underactive thyroid (hypothyroidism), leading to a slower metabolism.
What is Gioter and what causes it
-enlarged thyroid gland
-Iodine deficiency:
-Enzyme deficiency:
-Increased hormone needs: During puberty, pregnancy, or stress, the body may need more thyroid hormones, and the thyroid tries to produce more, leading to enlargement.
What is Thyroiditis
inflammation of the thyroid gland, caused by viral/ bacterial infections.
What is Hashimoto’s Thyroiditis:
-body attacks the thyroid gland.
-Autoantibodies and T-cells destroy the thyroid tissue and its receptors (where TSH normally works).
explain difference between Graves and Hashimoto’s
Unlike Graves’ disease, where the immune system stimulates the thyroid, Hashimoto’s damages it, leading to less thyroid hormone production, which causes hypothyroidism (low thyroid hormone).
Explain the 3 main types of follicular cell carcinoma
-Highly-differentiated follicular and papillary carcinoma:
Associated with radiation exposure, especially in children.
Good prognosis in young people but more aggressive in adults.
-Poorly differentiated follicular carcinomas:
These cancers still resemble thyroid tissue but are less differentiated.
They have a poor prognosis and grow rapidly with the ability to spread (metastasize).
Undifferentiated (anaplastic) carcinoma:
This type is rare and occurs in older adults.
The cancer cells grow very quickly, and it has a poor prognosis.
Explain Medullary carcinoma:
originates from parafollicular cells, which produce calcitonin.
can cause poor bone health (since calcitonin helps regulate calcium)
What do parathyroid gland do
regulate calcium and phosphate levels in the blood
Explain the process the parathyroid undergoes when blood calcium levels are low
parathyroid glands release parathyroid hormone (PTH) this:
-Release calcium from the bones into the bloodstream.
-Increase calcium absorption from the intestines.
-Decrease the amount of calcium excreted by the kidneys.
What does Calcitonin do
a hormone secreted by the thyroid, works in the opposite way to PTH. It helps to lower blood calcium levels when they are too high, but it has a lesser effect compared to PTH.
What is Hyperparathyroidism what does it cause
happens from hormone-secreting parathyroid adenoma causes increased calcium in blood, kindey stones, calcium buildup, heart arryhtmias/neurological effects.
Explain primary, secondary and teritary Hyperparathyroidism
Primary: from adenoma
Secondary: can result from chronic renal disease when too much calcium is lost
Teritary: chronic hyperparathyroidism (over 2y) – parathyroid becomes unresponsive to chronic low blood calcium levels and releases PTH constantly
Explain what Hypoparathyroidism is and how it happens
condition where the parathyroid glands don’t produce enough parathyroid hormone.
cna results from
-surgery
-autoimmune
-Congenital abnormalities
What are the effects of Hypoparathyroidism
Hypocalcemia: Blood calcium levels drop sharply.
this causes muscle aches, irregular heart rhythems.
Explain the 3 things that the Adrenal glands release.
Sugar, Salt, Sex
1)Glucocorticoids(cortisol):blood sugar by supressing fat and protein and helps supress inflammation.
2)Mineralocorticoids(Aldosterone):Regulate water and electrolyte balance.They help retain salt (sodium) and water to maintain blood pressure.
3)Gonadocorticoids (DHEA):They produce sex hormone precursors for testosterone and estrogen.
What does Adrenal cortical hypofunction cause
-Glucocorticoid deficiency: causes low blood sugar (hypoglycemia).
-Mineralocorticoid deficiency: leads to low blood volume and low blood pressure.
-Other effects include irregular or absent periods.
What is adrenal cortical hypofunction caused by
by atrophy or destruction of adrenal glands
usually autoimmune destruction is the cause – can also be due to TB , cancer or rare genetic defect
Explain Cushing disease
Results from excessive adrenal corticosteroid production.
Explain possible causes for cushings disease
-ACTH Hormone-producing pituitary microadenoma (Cushing disease – most common)
-Corticosteroid -producing adrenal cortex adenoma
-Hyperplastic adrenal glands or tumor
-Administration of large amounts of corticosteroid – used in immune suppression for autoimmune or transplant treatments
Overproduction of adrenal sex hormones can happen due to?
Congenital adrenal hyperplasia (CAH) is a condition where the adrenal glands don’t produce enough important hormones like aldosterone and cortisol. This happens because of a missing enzyme. To try to make up for this, the body starts producing a lot of a hormone called ACTH, which makes the adrenal glands overproduce testosterone. In males, this can cause early puberty, while in females, it can cause masculine traits like facial hair
What happens in Conn syndrom
here’s a tumor in the adrenal glands that makes too much aldosterone. This causes the kidneys to hold onto too much salt and water, which raises blood pressure. It also makes the body lose potassium, which can lead to muscle weakness.
What are the two inner part of the adrenal glands producing two important hormones
catecholamines: norepinephrine (noradrenaline) and epinephrine (adrenaline). These hormones are released into the bloodstream during times of stress, such as when you feel fear, anger, anxiety, or even during exercise. They prepare the body for the “fight or flight” response
What is pheochromocytoma
rare, usually benign tumor in the adrenal medulla that causes it to release too many catecholamines. This can lead to very high blood pressure
what are catecholamines
Group of hormones produced by the adrenal glands, specifically in the adrenal medulla (the inner part of the adrenal glands). The main catecholamines are:
-Epinephrine (Adrenaline) – Often called the “fight or flight” hormone
-Norepinephrine (Noradrenaline) – Works alongside epinephrine to increase heart rate and blood pressure. It’s also involved in regulating mood and focus.
-Dopamine – mood regulation, reward, and motor control.
How does Paraneoplastic syndrome happen?
when non-endocrine tumors (tumors not in the endocrine system) start producing hormones or hormone-like substances. These hormones may be identical to or mimic the action of real hormones in the body. usually in lungs, pancrease, CT.
state the order of the production of sex hormones
Hypothalamus → GnRH → Pituitary → FSH/LH → Gonads (Ovaries/Testes) → Sex hormones (Testosterone/Estrogen)
production of sex hormones is controlle dby
Controlled by gonadotropic hormones of pituitary gland FSH and LH
Explain how menstration occure and what hormones are involved
1)GnRH from the hypothalamus signals the anterior pituitary to release FSH and LH, which travel to the ovaries.
2)FSH helps small groups of follicles develop, but only one dominant follicle (with the most FSH receptors) will continue to grow and produce estrogen. The other follicles stop growing.
3)Estrogen causes ovulation (release of an egg) and thickens the endometrium (lining of the uterus) in preparation for possible pregnancy. It also causes a surge in GnRH, FSH, and LH to trigger ovulation.
4)After ovulation, the ruptured follicle turns into the corpus luteum, which produces progesterone to support the endometrium and prepare it for implantation.
5)If pregnancy doesn’t occur, the corpus luteum dies after about 2 weeks and turns into the corpus albicans, causing a drop in progesterone, and triggering menstruation.
