18 ENDOCRINE
How many hormones are produced by the posterior pituitary?
0 neurohypophysis can only release hormones, not produce ("synthesize")
synergistic effect
2 hormones with similar effects amplify the cell's response ex. FSH and testosterone
Where is the pineal gland located?
3rd ventricle of epithalamus
neurophypophysis hormones (posterior pituitary)
ADH - antidiuretic aka vasopressin Oxytocin
3 stages of GAS
Alarm reaction, resistance reaction, exhuastion
antidiuretic hormone (ADH)
Hormone produced by the neurosecretory cells in the hypothalamus that stimulates water reabsorption from kidney tubule cells into the blood and vasoconstriction of arterioles. posterior pituitary
Adenohypophysis (anterior pituitary) hormones
Hormones are: ACTH (adrenocorticotropic hormone), FSH (follicle-stimulating hormone), GH (growth hormone), LH (luteinizing hormone), Prolactin, and TSH (thyroid stimulating hormone)
hormone receptors
Hormones only affect target cells with specific membrane proteins called receptors
Addison's disease
Hyposecretion of glucocorticoids and mineralcorticoids adrenal disorder
Seratonin and Melatonin are derived from?
Tryptophan are amines
thyroid hormone (lipid) is synthesized from
Tyrosine
Paracrine chemical signaling
a cell targets a nearby cell
autocrine chemical signaling
a cell targets itself
adrenal glands
a pair of endocrine glands that sit just above the kidneys and secrete hormones (epinephrine and norepinephrine) that help arouse the body in times of stress.
General Adaptation Syndrome (GAS)
a three-stage physiological response that appears regardless of the stressor that is encountered aka STRESS RESPONSE
anterior pituitary
adenohypophysis
diabetes type 2
adult onset diabetes, non-insulin dependent, body produces insulin but no enough, is more common, can be controlled by diet.
Amines (water soluble)
all contain an amine group
pancreatic hormones
alpha - glucagon beta - insulin delta - somatostatin
water soluble hormones include
amine hormones, peptides, paracrines and autocrines (eicosanoids)
water soluble hormones
amines, peptides, paracrine (eicosanoids)/autocrine
hypophyseal portal system
blood travels from the hypothalamus to the anterior pituitary
The pancreas is
both an endocrine and exocrine gland
When hormones bind to receptors on a cell, they trigger a
cascade of actions within the cell that alter its physiological behavior
Hormones are
chemicals released into the bloodstream by endocrine glands "chemical messengers"
parathyroid glands are composed of
chief cells
pituitary disorders cause
children: hypo- dwarf hyper-giant adults: hypo- acromegaly hyper- diabetes insipidus
what is the purpose of the hypothalamus?
control the pituitary gland secretes releasing and inhibiting hormones link between nervous and endocrine systems
purpose of estrogen and progesterone
cycle regulation maintain preg sexual characteristics
Hypoparathyroidism
deficient production of parathyroid hormone - decreased calcium levels
steriod hormones
derived from cholesterol types: sex steroids corticosteroids
If an autoimmune disorder targets the alpha cells (pancreas), production of which hormone would be directly affected?
glucagon
Glucocorticoids (cortisol)
glucose metabolism and resist stress (Adrenocortical)
Down regulation makes the target cell
less sensitive to hormone
Which type of hormone requires a carrier protein in the blood?
lipid soluble
beta, insulin
lowers blood glucose
endocrine system function
maintain homeostasis works closely with the nervous system use hormones
the hypothalamus secretes releasing and inhibiting hormones that influence the
pituitary gland
parathyroid glands are located
posterior surface of the thyroid gland
Insulin, once bound to an insulin receptor, activates glucose receptors to ________ into the cell.
uptake glucose
What do hormones do?
•Alter activity (metabolism) of target cell •Alter plasma membrane permeability or voltage •Stimulate production of proteins/enzymes •Activate or deactivate enzymes •Stimulate mitosis •Induce secretory activity
hyperparathyroidism
Bones soften and deform formation of kidney stones
Cushing's syndrome
Caused by a tumor or high levels (hypersecretion) of cortisol adrenal disorder
Two sections of Adrenal Glands
Interior (medulla) produces adrenaline-like hormones. Outer (cortex) produces corticosteroids.
Thyroid follicles secrete
T3 and T4
thyroid hormones
T3, T4, C cells (calcitonin)
The secretion of thyroid hormones is controlled by ________.
TSH from the anterior pituitary gland
ADH
Target collecting ducts in the kidney and sweat glands - minimize water loss
peptides
amino acid and polypeptide all releasing and inhibiting from the hypothalamus ex. ADH Oxytocin HGH Insulin water soluble
Graves disease
an autoimmune disorder that is caused by hyperthyroidism and is characterized by goiter and/or exophthalmos
Hormones produced by the thymus play a role in the ________.
development of T cells
lipid soluble hormones ________ into cell.
diffuse
water soluble hormones can not
enter the cell due to the plasma membrane ---must use a second messenger
Adrenomedulla Hormones
epinephrine and norepinephrine - prolong sympathetic response sympathetic neurons innervate
Ovary hormones
estrogen and progesterone
The production of melatonin is inhibited by ________.
exposure to bright light
lipid soluble hormones are
hydrophobic use transport protien
thyroid hormones are regulated by
hypothalamo-hypophyseal-thyroid axis
Where do releasing hormones secrete from?
hypothalamus
The thyroid gland is located
immediately anterior to the trachea, inferior to larynx
alpha, glucagon
increase blood glucose
negative feedback loop
increased product inhibits secretion
parathyroid hormone
increases blood calcium levels, stimulates osteoclasts and inhibits osteoblasts
histamines
inflammation synthesized from histidine water soluble
Delta, somatostatin
inhibit insulin and glucagon
diabetes mellitus
insulin is not secreted adequately or tissues are resistant to its effects (pancreas disorder)
Where can lipid-soluble hormones act on the cell?
intracellular receptors
The hypothalamus is functionally and anatomically connected to the posterior pituitary lobe by a bridge of
nerve axons
A student is in a car accident, and although not hurt, immediately experiences pupil dilation, increased heart rate, and rapid breathing. What type of endocrine system stimulus did the student receive?
neural
hypothalamo-hypophyseal tract
neural connection between the hypothalamus and the posterior pituitary AXONS
posterior pituitary
neurohypophysis
Catecholamines
neurotransmitters- dopamine, norepinephrine, epinephrine water soluble Synthesized from tyrosine
antagonistic effect
one hormone opposes the action of another ex. insulin vs glucagon
water soluble hormone binds to receptor on the
outside of cell
If one hormone makes a target cell more responsive to another hormone that follows later, the first hormone is said to have a ___________ effect.
permissive
C cells
produce calcitonin decreases calcium in blood and stimulates osteoclasts
purpose of testes hormones
produce sperm sexual characteristics
Mineralcorticoids (aldosterone)
regulate Na/K concentrations (Adrenocortical)
What does the pineal gland produce?
seratonin
androgens and estrogens
sex hormones (Adrenocortical)
The thyroid gland consists of rings of ________________ surrounding colloid.
simple cuboidal follicle cells
lipid soluble hormones include
steroid and thyroid hormones
Oxytocin
stimulates uterine contractions during childbirth and milk secretion
down regulation
target cells lose receptors in response to the hormone response to high concentration decrease response ex. adipocytes and insulin
testes hormones
testosterone and androgens
When blood calcium levels are low, PTH stimulates ________.
the activity of osteoclasts
The adrenal cortex has __________ zones of cells that secrete different types of hormones.
three
A newly developed medication that disrupts hormonal activity has been observed to bind to an intracellular hormone receptor. If ingested, the medicine could disrupt levels of ________ hormone.
thyroid
T3 and T4
increase basal metabolic rate can help accelerate growth with (HGH)
goiter is caused by
iodine deficiency
Pancreas endocrine tissue is composed of
islets of Langerhans
Diabetes Type 1
juvenile diabetes, insulin dependent diabetes where the body produces little or no insulin. must inject insulin into the body.
What does the pineal gland secrete?
melatonin, derived from serotonin
Adrenocortical hormones
mineralocorticoids, glucocorticoids, androgens
neurophypophysis is
not a true gland - cant make hormones, only releases them
water soluble hormones use
second messenger (cAMP)
Endocrine glands ________.
secrete chemical messengers that travel in the bloodstream
lipid soluble hormones
steroid and thyroid hormones act on intracellular receptors that directly activate genes can enter cell
The adrenal medulla is modified nervous tissue of the
sympathetic nervous system fight or flight
up-regulation
target cells form more receptors in response to the hormone increase response greater sensitivity ex. oxytocin in late preg