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Definition
1) Nerve impulses/ Neurotransmitters
2) Faster responses, briefer effects, acts on specific target |
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Definition
1) Hormone – mediator molecule released in 1 part of the body but regulates activity of cells in other parts
2) Slower responses, effects last longer, broader influence |
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Definition
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Definition
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Term
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Definition
1) Pituitary, thyroid, parathyroid, adrenal and pineal glands
2) Hypothalamus, thymus, pancreas, ovaries, testes, kidneys, stomach, liver, small intestine, skin, heart, adipose tissue, and placenta not exclusively endocrine glands |
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Definition
| circulate in blood throughout body |
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Definition
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Definition
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Definition
| act on the same cell that secreted them |
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Term
| Chemical classes of hormones |
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Definition
1) Lipid-soluble
2) Water-soluble |
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Term
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Definition
use transport proteins:
1)Steroid
2)Thyroid
3)Nitric oxide (NO) |
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Term
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Definition
circulate in “free” form:
1) Amine
2) Peptide/ protein
3) Eicosanoid |
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Term
| Mechanisms of Hormone Action |
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Definition
| Response depends on both hormone and target cell |
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Term
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Definition
| bind to receptors inside target cells |
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Term
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Definition
bind to receptors on the plasma membrane:
1)Activates second messenger system
2)Amplification of original small signal |
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Term
| Responsiveness of target cell |
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Definition
depends on
1)Hormone’s concentration
2)Abundance of target cell receptors
3)Influence exerted by other hormones
Permissive, synergistic and antagonistic effects |
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Term
| Control of Hormone Secretion |
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Definition
1)Regulated by:
a)Signals from nervous system
b)Chemical changes in the blood
c)Other hormones
2)Most hormonal regulation by negative feedback
Few examples of positive feedback |
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Term
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Definition
| major link between nervous and endocrine system |
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Term
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Definition
attached to hypothalamus by infundibulum
1)Anterior pituitary or adenohypophysis
2)Posterior pituitary or neurohypophysis |
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Term
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Definition
Release of hormones stimulated by releasing and inhibiting hormones from the hypothalamus
Also regulated by negative feedback
Hypothalamic hormones made by neurosecretory cells transported by hypophyseal portal system
Anterior pituitary hormones that act on other endocrine systems called tropic hormones |
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Term
| Hormones of the Anterior Pituitary |
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Definition
1) Human growth hormone (hGH) or somatostatin
2) Thyroid-stimulating hormone (TSH) or thyrotropin
3) Follicle-stimulating hormone (FSH)
4) Luteinizing hormone (LH)
5) Prolactin (PRL)
6) Adrenocorticotropic hormone (ACTH) or corticotropin
7) Melanocyte-stimulating Hormone (MSH) |
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Term
| Human growth hormone (hGH) or somatostatin |
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Definition
| Stimulates secretion of insulin-like growth factors (IGFs) that promote growth, protein synthesis |
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Term
| Thyroid-stimulating hormone (TSH) or thyrotropin |
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Definition
| Stimulates synthesis and secretion of thyroid hormones by thyroid |
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Term
| Follicle-stimulating hormone (FSH) |
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Definition
| Ovaries initiates development of oocytes, testes stimulates testosterone production |
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Definition
| Ovaries stimulates ovulation, testes stimulates testosterone production |
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Definition
| Promotes milk secretion by mammary glands |
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Term
| Adrenocorticotropic hormone (ACTH) or corticotropin |
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Definition
| Stimulates glucocorticoid secretion by adrenal cortex |
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Term
| Melanocyte-stimulating Hormone (MSH) |
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Definition
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Term
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Definition
1) Does not synthesize hormones
2) Stores and releases hormones made by the hypothalamus
Transported along hypothalamohypophyseal tract
3) Oxytocin (OT)
4) Antidiuretic hormone (ADH) or vasopressin |
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Term
| Effects of hGH and IGFs [HYPOGLYCEMIA] |
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Definition
1) Low blood glucose (hypoglycemia)
stimulates release of GHRH
2) GHRH stimulates secretion of hGH by
somatotrophs
3) hGH and IGFs speed up breakdown of liver glycogen into glucose, which enters the blood more rapidly
4) Blood glucose level rises to normal
(about 90 mg/100 mL)
5) If blood glucose continues to increase, hyperglycemia inhibits
release of GHRH |
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Term
| Effects of hGH and IGFs [HYPERGLYCEMIA] |
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Definition
1) High blood glucose (hyperglycemia)
stimulates release of GHIH (human growth inhibitor hormone)
2) GHIH inhibits secretion of hGH by
somatotrophs
3) A low level of hGH and IGFs decreases the rate of glycogen breakdown
in the liver and glucose enters the blood more slowly
4) Blood glucose level falls to normal
(about 90 mg/100 mL)
5) If blood glucose continues to decrease, hypoglycemia inhibits
release of GHIH |
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Term
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Definition
1) During and after delivery of baby affects uterus and breasts
2) Enhances smooth muscle contraction in wall of uterus
3) Stimulates milk ejection from mammary glands |
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Term
| Antidiuretic Hormone (ADH) |
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Definition
1) Decreases urine production by causing the kindeys to return more water to the blood
2) Also decreases water lost through sweating and constriction of arterioles which increases blood pressure (vasopressin) |
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Term
MECHANISM OF Antidiuretic Hormone (ADH)
[High blood osmotic pressure ] |
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Definition
1) High blood osmotic pressure stimulates
hypothalamic osmoreceptors
2) Osmoreceptors activate the
neurosecretory cells that synthesize and
release ADH
3) Nerve impulses liberate ADH from
axon terminals in the posterior
pituitary into the bloodstream
4) Kidneys retain more water,
which decreases urine output
a) Sudoriferous (sweat) glands
decrease water loss by perspiration
from the skin
b) Arterioles constrict, which increases blood pressure |
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Term
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Definition
1) Located inferior to larynx
2) 2 lobes connected by isthmus
3) Thyroid follicles produce thyroid hormones
a) Thyroxine or tetraiodothyronine (T4)
b) Triiodothyronine (T3)
Both increase BMR, stimulate protein synthesis, increase use of glucose and fatty acids for ATP production
4) Parafollicular cells or C cells produce calcitonin
Lowers blood Ca2+ by inhibiting bone resorption |
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Term
| Control of thyroid hormone secretion |
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Definition
1) Thyrotropin-releasing hormone (TRH) from hypothalamus
2) Thyroid-stimulating hormone (TSH) from anterior pituitary
3) Situations that increase ATP demand also increase secretion of thyroid hormones |
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Term
| Thyrotropin releasing hormone(TRH) |
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Definition
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Term
| Thyroid-stimulating hormone (TSH) |
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Definition
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Term
| mechanism of Control of thyroid hormone secretion [low blood levels of T3/T4] |
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Definition
1) Low blood levels of T3 and T4 or low metabolic rate stimulate release of TRH
2) TRH, carried by hypophyseal portal veins to anterior pituitary, stimulates
release of TSH by thyrotrophs
3) TSH released into blood stimulates
thyroid follicular cells
4) T3 and T4 released into blood by
follicular cells
5) Elevated T3 inhibits release of
TRH and TSH (negative feedback) |
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Term
| Actions of Thyroid Hormones |
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Definition
1) Increase basal metabolic rate
2) Stimulate synthesis of Na+/K+ ATPase
3) Increase body temperature (calorigenic effect)
4) Stimulate protein synthesis
5) Increase the use of glucose and fatty acids for ATP production
6) Stimulate lipolysis
7) Enhance some actions of catecholamines
8) Regulate development and growth of nervous tissue and bones |
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Term
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Definition
1)Embedded in lobes of thyroid gland
Usually 4
2)Parathyroid hormone (PTH) or parathormone
3)Blood calcium level directly controls secretion of both calcitonin and PTH via negative feedback |
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Term
| Parathyroid hormone (PTH) or parathormone |
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Definition
1)Major regulator of calcium, magnesium, and phosphate ions in the blood
2)Increases number and activity of osteoclasts
3)Elevates bone resorption |
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Term
| Roles of Calcitonin (CT), Parathyroid hormone, Calcitrol in Calcium Homeostasis |
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Definition
1) High level of Ca2+ in blood stimulates thyroid gland parafollicular cells to release more CT
2) CALCITONIN inhibits osteoclasts, thus decreasing blood Ca2+ level. |
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Term
| Roles of Calcitonin (CT), Parathyroid hormone(PTH), Calcitrol in Calcium Homeostasis |
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Definition
1) Low level of Ca2+ in blood stimulates parathyroid gland chief cells to release more PTH.
2) PARATHYROID HORMONE (PTH) promotes release of Ca2+ from bone extracellular matrix into blood and slows loss of Ca2+ in urine, thus increasing blood
Ca2+ level.
3) PTH also stimulates the kidneys to release CALCITRIOL.
4) CALCITRIOL stimulates increased absorption of Ca2+ from foods, which
increases blood Ca2+ level. |
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Term
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Definition
stimulates increased absorption of
Ca2+ from foods, which increases blood Ca2+ level. |
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Term
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Definition
structurally and functionally distinct regions:
1) Adrenal cortex
2) Adrenal medulla |
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Term
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Definition
1) Mineralocorticoids affect mineral homeostasis
2) Glucocorticoids affect glucose homeostasis
cortisol
3) Androgens have masculinzing effects
Dehydroepiandrosterone (DHEA) only important in females |
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Term
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Definition
1) Modified sympathetic ganglion of autonomic nervous system
2) Intensifies sympathetic responses
3) Epinephrine and norepinephrine |
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Term
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Definition
1) Both exocrine and endocrine gland
2) Roughly 99% of cells produce digestive enzymes
3) Pancreatic islets or islets of Langerhans |
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Term
| Pancreatic islets or islets of Langerhans |
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Definition
1) Alpha or A cells secrete glucagon – raises blood sugar
2) Beta or B cells secrete insulin – lowers blood sugar
3) Delta or D cells secrete somatostatin – inhibits both insulin and glucagon
4) F cells secrete pancreatic polypeptide – inhibits somatostatin, gallbladder contraction, and secretion of pancreatic digestive enzymes |
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Definition
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Term
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Definition
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Definition
| inhibits both insulin and glucagon |
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Term
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Definition
| inhibits somatostatin, gallbladder contraction, and secretion of pancreatic digestive enzymes |
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Term
| Regulation of Glucagon (hypoglycemia) |
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Definition
1) Low blood glucose (hypoglycemia) stimulates alpha cells to secrete GLUCAGON
2) Glucagon acts on hepatocytes (liver cells) to:
a) convert glycogen into glucose
(glycogenolysis)
• form glucose from lactic acid and
certain amino acids (gluconeogenesis)
3) Glucose released by hepatocytes
raises blood glucose level to normal
4) If blood glucose continues to rise,
hyperglycemia inhibits release of glucagon |
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Term
| Regulation of Insulin (hyperglycemia) |
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Definition
1) High blood glucose (hyperglycemia)
stimulates beta cells to secrete
INSULIN
2) Insulin acts on various body cells to:
• accelerate facilitated diffusion of glucose into cells
• speed conversion of glucose into glycogen (glycogenesis)
• increase uptake of amino acids and increase protein synthesis
• speed synthesis of fatty acids (lipogenesis)
• slow glycogenolysis
• slow gluconeogenesis
3) Blood glucose level falls
4) If blood glucose continues to fall, hypoglycemia inhibits release of insulin |
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Term
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Definition
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Term
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Definition
| convert glycogen into glucose by hydrolysis |
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Term
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Definition
form glucose from lactic acid and
certain amino acids |
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Term
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Definition
| speed conversion of glucose into glycogen |
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Term
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Definition
1) produce 2 estrogens (estradiol and estrone) and progesterone
A) With FSH and LH regulate menstrual cycle, maintain pregnancy, prepare mammary glands for lactation, maintain female secondary sex characteristics
B) Inhibin inhibits FSH
C) Relaxin produced during pregnancy |
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Term
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Definition
1) produce testosterone – regulates sperm production and maintains male secondary sex characteristics
a) Inhibin inhibits FSH |
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Definition
| produce gametes and hormones |
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Term
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Definition
1) Attached to roof of 3rd ventricle of brain at midline
2) Masses of neuroglia and pinealocytes
3) Melatonin – amine hormone derived from serotonin
4) Appears to contribute to setting biological clock
4) More melatonin liberated during darkness than light |
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Term
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Definition
1) Located behind sternum between the lungs
2) Produces thymosin, thymic humoral factor (THF), thymic factor (TF), and thymopoietin
3) All involved in T cell maturation |
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Term
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Definition
| promotes the development of immune-system cells. |
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Term
| thymic humoral factor (THF) |
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Definition
| a humoral factor secreted by the thymus, which promotes the maturation of T lymphocytes |
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Term
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Definition
| a polypeptide hormone secreted by thymic epithelial cells that induces differentiation of precursor lymphocytes into thymocytes. |
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Term
| Thyroxine or tetraiodothyronine (T4) |
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Definition
| increase BMR, stimulate protein synthesis, increase use of glucose and fatty acids for ATP production |
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Term
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Definition
| increase BMR, stimulate protein synthesis, increase use of glucose and fatty acids for ATP production |
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Term
| Parafollicular cells or C cells |
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Definition
produce calcitonin
Lowers blood Ca2+ by inhibiting bone resorption |
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Definition
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Term
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Definition
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Term
| Stressful conditions can result in stress response or general adaptation syndrome (GAS) |
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Definition
1) 3 stages – initial flight-or-fight, slower resistance reaction, eventually exhaustion
2) Prolonged exposure to cortisol can result in wasting of muscles, suppression of immune system, ulceration of GI tract, and failure of pancreatic beta cells |
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Term
| Cortisol "stress hormone" |
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Definition
produce by adrenal gland:
* Proper glucose metabolism
* Regulation of blood pressure
* Insulin release for blood sugar maintanence
* Immune function
* Inflammatory response |
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Term
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Definition
* Impaired cognitive performance
* Suppressed thyroid function
* Blood sugar imbalances such as hyperglycemia
* Decreased bone density
* Decrease in muscle tissue
* Higher blood pressure
* Lowered immunity and inflammatory responses in the body, slowed wound healing, and other health consequences
* Increased abdominal fat, which is associated with a greater amount of health problems than fat deposited in other areas of the body. Some of the health problems associated with increased stomach fat are heart attacks, strokes, the development of metabolic syndrome, higher levels of “bad” cholesterol (LDL) and lower levels of “good” cholesterol (HDL), which can lead to other health problems! |
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Term
| ADRENAL MEDULLA (STRESS RESPONSE) |
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Definition
EPINEPHRINE/NOREPINEPHRINE
1) increased heart rate
2) constriction of blood vessels of most viscera and skin
3) dilation of blood vessels
4) contraction of spleen
5) conversion of glycogen to glucose in liver
6) sweating
7) dilation of air way
8) decrease in digestive activities
9) water retention and elevated blood pressure |
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Term
| ACTH (ADRINOCORTICOTROPIC HORMONE) >ADRENAL CORTEX > CORTISOL |
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Definition
1) LIPOLYSIS
2) GLUCONEOGENESIS
3) PROTEIN CATABOLISM
4) SENSITIZE BLOOD VESSEL
5) REDUCED INFLAMMATION
) |
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Term
| hGH > LIVER > IGFs > tress reponse |
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Definition
1) LIPOLYSIS
2) GLYCOGENOLYSIS |
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Term
| TSH > thyroid glands > thyroid hormones (T3/T4) > tress reponse |
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Definition
| INCREASED USE OF GLUCOSE TO PRODUCE ATP |
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