Exam 6: Endocrine Flashcards
What is the function of FSH ?
Follicle Stimulating Hormone (FSH)
Produced and secreted: Anterior Pituitary
Function: Growth of the ovarian follicles, production of estrogen in females; & production of sperm in males.
What is the function for FSH in male vs female ?
Male: Production of sperm
Female: Growth of ovarian follicles (containing egg) & stimulates secretion of ovarian sex hormones like estrogen
If the parathyroid gets triggered, what happens ?
Parathyroid regulates the amount of calcium in the blood.
It secretes parathyroid hormone (PTH) which triggers the release of calcium into the blood (opposite effect of calcitonin from thyroid) to maintain proper levels of circulating calcium.
What does ACTH stimulate ?
ACTH= Adrenocorticotropic Hormone
Produced & Secreted by: Anterior Pituitary Gland
Function: stimulates the growth of the adrenal gland
What does ACTH Release? Which Hormone ?
ACTH triggers the production and release of Cortisol in the adrenal gland
What is adolsterone ?
- Produced by: Zona Glomerulosa (Adrenal Cortex in Andrenal Gland) within in the kidney
- Structure: Steroid Hormone
- Function: primary mineraloraeito- regulates salt and water in the body (has an effect on blood pressure). Regulates electrolyte concentrations.
What is the function of the ADH hormone ?
- Antidiuretic Hormone (ADH) AKA Vasopressin
- Produced by: Supraoptic Nuclei in the Hypothalamus
- Stored & Secreted by: Posterior Pituitary
- Function: Increases water retention, thus reducing urine volume, and preventing dehydration. Also called vasopressin because it can cause vasoconstriction.
Which hormone increases blood sugar as it begins breaking down fat ?
Glucagon is secreted by the alpha cells in the pancreas and raises blood sugar
In adipose tissue, it stimulates fat catabolism and release of free fatty acids
Which endocrine gland atrophy’s with age ?
The thymus slowly shrinks with age post puberty and becomes replaced with fat.
What does calcitonin do ?
Controls (lowers) calcium and potassium levels by inhibiting osteoclasts, the cells that break down bone. When osteoclasts break down bone tissue, the calcium enters the blood stream
What is a hormone ?
Chemical messengers that travel in the bloodstream to other tissues and organs that regulate metabolic function
What is the function of glycogen and glucagon ?
Glycogen= polysaccharide Glucagon = hormone
In liver Glucagon stimulates gluconeogenesis, glycogenolysis, and the release of glucose into the circulation raising blood glucose level by breaking down glycogen.
Which hormones are secreted by the pituitary gland ?
Anterior (6 Hormones):
- Follicle Stimulating Hormone (FSH): secreted by the gonadotropiic cells- stimulates secretion of ovarian sex hormones and development of ovarian follicles (that contain the egg) in female AND sperm production in male.
- Lutenizing Hormone (LH): secreted by the gonadotropiic cells- stimulates ovulation & stimulates secretion of progesterone (important to pregnancy) in females AND stimulates testes to secrete testosterone in male
- Thyroid Stimulating Hormone (TSH): secreed by the thyrotropic cells- stimulates secretion of thyroid hormone (effects on metabolic rate, body temp, etc) AND stimulates growth of the thyroid gland
- Adrenocorticotrophic Hormone (ACTH) or corticotropin- secreted by the corticotropic cells- stimulates adrenal cortex to secrete glucocorticoids (especially cortisol) which regulates glucose, protein, and fat metabolism and are important to body’s response to stress.
- Prolactic (PRL): secreted by prolactin cells- after birth, stimulates mammary glands to synthesize milk
- Growth Hormone (GH) or somatotropin: secreted by the somatotropic cells, most numerous cells of the anterior pituitary. stimulates mitosis and cellular differentiation to promote tissue growth throughout the body.
Posterior (2 Hormones- both produced by the hypothalamus):
- Antidiuretic Hormone (ADH):Increases water retention, thus reducing urine volume, and preventing dehydration
- Oxytocin (OT): sexual arousal/ orgasm, sexual satisfaction, emotional bonding, labor contractions, flow of milk during lactation, emotional bonding btw. mother and infant
Glucocorticoids
-Secreted by zona fasciculata and zona reticulata in response to ACTH
-Regulate metabolism of glucose and other fuels
Cortisol and corticosterone stimulate fat and protein catabolism, gluconeogenesis (glucose from amino acids and fatty acids) and release of fatty acids and glucose into blood
-Help body adapt to stress and repair tissues
-Anti-inflammatory effect becomes immune suppression with long-term use
Stress hormone that comes from the adrenal cortex.
If you have insufficient dietary iodine what can it cause?
Endemic goiter (disease occurs in a geographic locality) -Dietary iodine deficiency, no TH, no feedback, increased TSH stimulates hypertrophy
Myxedema-
Why is iodine a essential element for synthesis of thyroxine
Iodine, as a trace element, is a necessary and limiting substrate for thyroid gland hormone synthesis. It is an essential element that enables the thyroid gland to produce thyroid hormones thyroxine (T4) and triiodothyronine (T3)
What is LH?
Luteinizing hormone (LH) Stimulates ovulation, stimulates corpus luteum to secrete progesterone, stimulates testes to secrete testosterone
What is Thyroxine ?
AKA T4
A hormone that is made by the thyroid gland and contains iodine. Thyroxine increases the rate of chemical reactions in cells and helps control growth and development.
What is Oxytocin?
-Produced by the posterior pituitary
Hormone: labor,
- Stimulates labor contractions during childbirth
- Stimulates flow of milk during lactation
Neuro:
- Surge of hormone released during sexual arousal and orgasm
- Promotes feelings of sexual satisfaction and emotional -bonding between partners
-May promote emotional bonding between lactating mother and infant
What is Testosterone ?
- Testosterone and other steroids from interstitial cells nestled between the tubules
- Stimulates development of male reproductive system in fetus and adolescent, and sex drive
- Sustains sperm production
What is Growth Hormone?
- Produced & secreted by the anterior pituitary
- Stimulates mitosis and cellular differentiation; bones/ cartilage/ muscles growth
What is Parathyroid Hormone?
-PTH
- Secreted by Parathyroid Glands
- Increases blood Ca^(2+) levels by increasing osteoclast activity (opposite of calcitonin)
- Promotes synthesis of calcitriol
- Increases absorption of Ca^(2+)
- Decreases urinary excretion
- Increases bone resorption
What is Gonadotropin ?
Two hormones secerted by the anterior pituitary that target the gonads. **Same as LH
Follicle-stimulating hormone (FSH)
Stimulates secretion of ovarian sex hormones, development of ovarian follicles, and sperm production
Luteinizing hormone (LH)
Stimulates ovulation, stimulates corpus luteum to secrete progesterone, stimulates testes to secrete testosterone
What is letptin and what is it secreted by ?
Location: Adipose tissue (adipocytes) secretes leptin
Function:
The central function of leptin is metabolic homeostasis that can be attained by the delivery of information about the total body fat mass to the hypothalamus that in turn alters the CNS function and regulates glucocorticoids, insulin hormone and food intake & energy balance
**Suppresses Appetite
Addison’s Disease
Damage to the adrenal cortex
Hyposecretion of the adrenal cortex- produces too little steroid hormone adolsterone and cortisol.
Cortisol regulates the body’s reaction to stressful situations. Aldosterone helps with sodium and potassium regulation. The adrenal cortex also produces sex hormones (androgens).
Symptoms: muscle weakness fatigue and tiredness darkening in skin color weight loss or decreased appetite a decrease in heart rate or blood pressure low blood sugar levels fainting spells sores in the mouth cravings for salt nausea vomiting
Cushing’s Disease
Hypersecretion of the adrenal cortex (cortisol levels are affected)
Can be caused by ACTH overstimulation or glucocorticoid therapy
Symptoms:
Moon Face
Hyperglycemia
High Blood Pressure
Diabetes
Hyposecretion of insulin (pancreas)
Dwarfism
Hyposecretion of Growth Hormone
Acromegaly
Hypersecretion of Growth Hormone
Graves
Autoimmune disease involving the thyroid (all hormones)
Hyperthyrodism
Symptoms
- bulging eyes (inflammation)
- cant gain weight
- excessive heat
- racing heartbeat
- muscle weakness
Creitism
Hyposecretion of thryoid in infants (all hormones)
Cause: iodine deficiency
Symptoms:
- failure to grow/ develop
- CNS dysfunction
- mental retardation
Treatment: iodine
-skeltal deformities
Myxedema
Hyposecretion of thyroid in adults
Cause:
Symptoms: Hypothermia Decreased breathing Lower than normal sodium levels Low blood oxygen levels
Myxedema
Hyposecretion of thyroid in adults
Thyroids are removed- not producing hormones
Hypothalamic Releasing & Inhibiting Hormones that regulate the anterior pituitary:
- Thyrotropin Releasing Hormone (TRH): promotes secretion of thyroid stimulating hormone TSH & Prolactin (PRL)
- Corticotropin Releasing Hormone (CRH): Promotes secretion of adrenocorticotropic hormone (ACTH)
- Gonadotropin Releasing Hormone (GnRH): Promotes secretion of follicle stimulating hormones & lutenizing hormone (LH)
- Growth Hormone Releasing Hormone (GHRH): Promotes secretion of growth hormone (GH)
- Prolactin Inhibiting Hormone (PIH): Inhibits secretion of prolactin
- Somatostatin: Inhibits secretion of growth hormone (GH) and thyroid stimulating hormone (TSH)
Thymus & Hormones
- Located by sternum
- Reduces in size as we grow up & replaced with fat
- Involved in endocrine, lymphatic, and immune functions
- Releases Thymopoietin, Thymosin, and Thymulin: all stimulate the development and activity of T cells which are involved in the body’s immune system.
Thyroid & Hormones
- Wrapped around trachea
- Releases Thryoid Hormone (T3 and T4): involved in influencing metabolic rate by raising oxygen consumption and increasing heat production; heart rate; and respiratory rate, and strength of heartbeat
- TH also respond to rising levels of blood calcium by secreting calcitonin, which stimulates osteoblast activity (uses calcium for bone growth)
Parathyroid & Hormones
- Embedded in the posterior surface of thyroid
- Not affected by the pituitary gland but directly monitor blood composition
- Secrete parathyroid homrone (PTH) which regulates blood calcium levels– will raise levels of calcium in blood when too low.
Adrenal Glands & Hormones
-Sits on top of of the kidneys
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Adrenal Medulla
- Acts as an endocrine gland & ganglion of the sympathetic nervous system
- Pain, Fear, and Stress will cause stimulation of Chromaffin cells within the adrenal medulla will secrete norepinephrine, epinephrine, and some dopamine
- These hormones increase alertness and prepare the body in several ways for physical activity ie/ raise blood pressure, stimulate circulation, raise metabolic rate, Glycogenisis (glyogen into glucose) and Glucogenisis (fats, aminos, and other carbs into glucose)
Adrenal Cortex Layers & Hormones
- Zona Glomerulosa (outer): adolsterone- falling blood pressure leads to secretion of this hormone and adolsterone will act on kidney to retain sodium to faciliate water retention via osmosis.
- Zona Fasciciulata (middle): Glucocorticoids (cortisol and corticostreone): released in response to ACTH from pituiraty - stimulate glucogensis (fat breakdown into glucose) and glucose release to help with stress & repair damaged tissues. Also release androgens, see below.
- Zona Reticularis (inner): Androgens (ie: Dehyroepiandosterone (DHEA) / Estrogen release in response to ACTH. DHEA involved in prenatal development of male reproductive tract. DHEA also indcuces growth of pubc and axillary hair during puberty and sex drive throughout life.
Pancreas and hormones
- Located below stomach
- Alpha cells = glucagon cells secrete glucagon. Glucagon promotes glycogensis (breakdown of glycogen into glucose) AND gluconeogensis (synthesis of glucose from fats and proteins)
- Beta Cells = insulin cells secrete insulin and Amylin. Anatognizes glucagon. Insulin promotes glycogen synthesis in the liver.
- Delta Cells or somatostatin cells- secrete somatostatin. Helps regulate the speed of digestion and nutrient absortption.
- PP cells secrete pancreatic polypeptide (PP) 4-5 hours after a meal by. PP inhibits stimulation of the pancreas by the vagus nerve.
Hyperglycemic Hormone vs Hypoglycemic Hormone
Hyperglycemic Hormone: any hormone that raises blood glucose concentration
Hypoglycemic Hormone: any hormone that lowers blood glucose concentration
The Gonads & Hormones
Ovaries Secrete: estradiol, progresterone, and inhibin
Testes secrete: testerone, lesser extents androgens and estrogens, and inhibin. Testerone stimulates development of male reproductive system in fetus and adolscence. It also sustains sperm production and sexual instinct through adult life.
