Download Chapter 45 - Endocrine

Chapter 26: Regulation Part I - The Endocrine System
NEW AIM: How do chemical signals coordinate body functions?
I. Exocrine vs. Endocrine glands
A. Exocrine
- have ducts (tubes made of cells) that carry secretion products to an outside surface
Ex. Sweat (eccrine), sebaceous, mammary, digestive (pancreas, liver, gall bladder), etc…
Remember that the lining of your digestive tract, nephron tubules, etc… are external surfaces
– you do not need to cross any cell layers to get there.
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
I. Exocrine vs. Endocrine glands
B. Endocrine
- ductless, hormones secreted into blood
- IMPORTANT: hormones circulate and influence ONLY
cells with receptors for them (target cells)
- >50 known hormones in vertebrates
There are two main types of
hormone secreting cells
1. Endocrine cells, which typically secrete their
hormone in response to a chemical stimulus like a
ligand or an environmental change like high
glucose levels that triggers signal transduction.
2. Neurosecretory cells, which are neurons (wirelike cells that transmit electrical signals) that
secrete hormones. These cells are typically
activated by an electrical signal and use electrical
signals to secrete their hormones. Most are found
in the hypothalamus – the master endocrine organ
Fig. 26.1
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
A. Endocrine glands
B. Chemical regulatory system of body
Ex. Regulates metabolic rate, growth,
maturation, reproduction, blood
glucose, blood calcium, etc…
Nervous system = other regulatory system
of body
Why do we need two regulatory systems?
Endocrine = slower and more prolonged
(long-lasting) effect
Both systems work closely together
(interdependent)
Fig. 26.3
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
D. Amino acid based vs. steroid hormones
i. Amino acid based (3 types)
1. amine (modified amino acid) - ex. epinephrine
2. Peptide - ex. gastrin
3. protein hormones - ex. insulin
epinephrine
gastrin
insulin
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
D. Amino acid based vs. steroid hormones
i. Amino acid based (3 types)
1. amine (modified amino acid)
2. Peptide
3. protein hormones
How do amino acid based hormones “talk” to cells?
4. Bind and activate surface receptors
(can’t cross PM)
5. Result: Turn genes On/Off or
activate/deactivate enzymes, etc…
Fig. 26.2
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
D. Amino acid based vs. steroid hormones
ii. Steroid hormone
1. Lipids made from cholesterol
Ex. Testosterone and estrogen
cholesterol
testosterone
estrogen
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
D. Amino acid based vs. steroid hormones
ii. Steroid hormone
1. Lipids made from cholesterol
Ex. Testosterone and estrogen
How do steroid hormones “talk” to cells?
2. Cytoplasmic receptor protein
3. Receptor protein usually a
transcription factor
4. Turn genes ON/OFF ONLY
Fig. 26.2
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
D. Amino acid based vs. steroid hormones
Fig. 26.2
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
D. Amino acid based vs. steroid hormones
iii. Exception to the rule
a. Thyroxine (T4) and triiodothyronine (T3)
- amine hormones
- produced by thyroid
- relatively non-polar, behave like steroids
triiodothyronine (T3)
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
E. Endocrine glands of vertebrates
i. Some have ONLY endocrine
function
Ex. Thyroid and pituitary
ii. Some also have a non-endocrine
function
Ex. pancreas
Exocrine = digestive enzymes
Endocrine = insulin release
Fig. 26.3
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
E. Major vertebrate endocrine glands and their hormones
Pg. 521
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
E. Major vertebrate endocrine glands and their hormones
Pg. 521
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
E. Major vertebrate endocrine glands and their hormones
i. Steroid hormones made only by sex
organs (testes and ovaries) and adrenal
glands (specifically the adrenal cortex)
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
F. The hypothalamus
i. Part of brain
ii. Master control center of endocrine system
iii. Connects nervous system to endocrine system
- receives info from nerves about internal and external environment
iv. Closely tied to pituitary gland – in fact, the posterior
pituitary is made of cells that extend from the hypothalamus
Fig. 26.4
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
F. The Pituitary
i. Two parts
1. Posterior lobe (posterior pituitary)
- composed of nervous tissue (extension of hypothalamus)
- Made of neurosecretory cells
- stores and secretes hormones made in hypothalamus
Fig. 26.4
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
F. The Pituitary
i. Two parts
2. Anterior lobe (anterior pituitary)
a. composed of NON-nervous glandular tissue (endocrine cells)
b. synthesizes own hormones, most control other endocrine glands
c. hormone release controlled by…Hypothalamus hormones
Fig. 26.4
Chapter 26: Regulation Part I - The Endocrine System
NEW AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
F. The Pituitary
i. Two parts
2. Anterior lobe (anterior pituitary)
a. composed of NON-nervous glandular tissue
b. synthesizes own hormones, most control other endocrine glands
c. hormone release controlled by…Hypothalamus hormones
- Hypothalamus hormones that control AP
1. Releasing hormones
- Bunch of different hormones that signal AP to
release a certain hormone
2. Inhibiting hormones
- Bunch of different hormones that signal AP to
stop releasing a certain hormone
Chapter 26: Regulation Part I - The Endocrine System
NEW AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
G. Example you need to know: Hypothalamus and AP interaction (Example)
1. cold external temperature
2. Hypothalmus secretes TRH into blood
TRH = TSH releasing hormone
3. TRH stimulates AP to secrete TSH
(thyroid stimulating hormone) into blood
4. TSH stimulates thyroid to secrete the
hormone thyroxine (T4) into the blood
5. Thyroxine (T4) binds to thyroxine
receptors, which are found on most cells
instructing them to increases metabolic
rate of body cells – heat generated
6. Thyroxine (T4) and TSH inhibit
hypothalamus from secreting TRH
NEGATIVE FEEDBACK
(hypothalamus regulates body temp through thyroid)
Hypothalamus hormones
Fig. 26.4
Chapter 26: Regulation Part I - The Endocrine System
NEW AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
G. Example you need to know: Hypothalamus and AP interaction (Example)
1. cold external temperature
2. Hypothalmus secretes TRH into blood
TRH = TSH releasing hormone
3. TRH stimulates AP to secrete TSH
(thyroid stimulating hormone) into blood
4. TSH stimulates thyroid to secrete the
hormone thyroxine (T4) into the blood
5. Thyroxine (T4) binds to thyroxine
receptors, which are found on most cells
instructing them to increases metabolic
rate of body cells – heat generated
6. Thyroxine (T4) and TSH inhibit
hypothalamus from secreting TRH
NEGATIVE FEEDBACK
(hypothalamus regulates body temp through thyroid)
Chapter 26: Regulation Part I - The Endocrine System
NEW AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
H. The Hypothalamus and Posterior pituitary (PP)
i. REMINDER: hormones made in hypothalamus
and stored/released in PP
ii. Neurosecretory cells extend into PP where
they secrete hormone into blood
1. oxytocin
- causes uterine muscles to contract
during child birth – polypeptide hormone
Target organs
(the organs
targeted by the
hormone)
It is typically administered intravenously
immediately after child birth as well to keep the
contractions going to make sure the placenta
comes out / is delivered.
- mammary glands to pump milk
2. ADH (antidiuretic hormone or vasopressin)
- Target organs are kidneys - reabsorb water
from collecting duct of nephrons
- Polypeptide hormone, see excretory system
Fig. 26.5
Chapter 26: Regulation Part I - The Endocrine System
NEW AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
I. The Hypothalamus and Anterior
pituitary (AP)
- neurosecretory cells of hypothalamus
secrete RH or IH (releasing hormone / inhibitory hormone)
- blood carries RH/IH to AP to control hormone
secretion – each hormone released by AP is
contolled by a different RH/IH
1. Hormones from AP that control other
endocrine glands:
TSH - thyroid stimulating hormone
ACTH - adrenocorticotropic hormone
FSH - follicle stimulating hormone
LH - luteinizing hormone
2. Other hormones
GH - growth hormone
PRL - prolactin
Endorphins (endogenous morphine)
FLAGTEP
Fig. 26.5
Chapter 26: Regulation Part I - The Endocrine System
NEW AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
I. The Hypothalamus and Anterior
pituitary (AP)
- neurosecretory cells of hypothalamus
secrete RH or IH (releasing hormone / inhibitory hormone)
2. Other hormones
GH - growth hormone
PRL - prolactin
Endorphins
Human Growth Hormone (hGH) is a protein.
It targets many cells and stimulates growth of
these cells as well as mitotic division. As you
might have hypothesized, levels of GH in the
blood fall off with age.
FLAGTEP
Fig. 26.5
Chapter 26: Regulation Part I - The Endocrine System
NEW AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
I. The Hypothalamus and Anterior
pituitary (AP)
- neurosecretory cells of hypothalamus
secrete RH or IH (releasing hormone / inhibitory hormone)
2. Other hormones
GH - growth hormone
PRL - prolactin
Endorphins
Prolactin is a protein as well. It promotes
lactation (production of milk) in females.
FLAGTEP
Fig. 26.5
Chapter 26: Regulation Part I - The Endocrine System
NEW AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
I. The Hypothalamus and Anterior
pituitary (AP)
- neurosecretory cells of hypothalamus
secrete RH or IH (releasing hormone / inhibitory hormone)
2. Other hormones
GH - growth hormone
PRL - prolactin
Endorphins
Beta-endorphin: A 31 amino acid polypeptide.
Endorphins are neurotransmitters, which
means they talk to neurons and tell them to fire
or not to fire. We will discuss this in detail with
the nervous system. In general, endorphins
are released during exercise, excitement, and
pain and bring about feelings of well being and
pain reduction similar to morphine (endo –
form within, orphin – morphine = endorphine)
FLAGTEP
Fig. 26.5
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
J. Thyroid
1. located just below larynx
2. Hormones produced (amine)
- Thyroxine T4
- Triidodthyronine T3
triiodothyronine (T3)
Both contain iodine
Fig. 26.3
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
J. Thyroid
1. located just below larynx
2. Hormones produced (amine)
- Thyroxine T4
- Triidodthyronine T3
triiodothyronine (T3)
Both contain iodine
Remember the Goiter - lack of iodine in diet – causes thyroid to swell
like a balloon as it tries to make T3 and T4 under excessive TSH
stimulation.
Fig. 26.6A
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
Fig. 26.6
II. The Endocrine System
J. Thyroid
1. located just below larynx
2. Hormones produced (amine)
- Thyroxine T4
- Triidodthyronine T3
Goiter - lack of iodine in diet
Why a goiter forms
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
Fig. 26.6
II. The Endocrine System
J. Thyroid
1. located just below larynx
2. Hormones produced (amine)
- Thyroxine T4
- Triidodthyronine T3
Goiter - lack of iodine in diet
Why a goiter forms
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
Fig. 26.6
II. The Endocrine System
J. Thyroid
1. located just below larynx
2. Hormones produced (amine)
- Thyroxine T4
- Triidodthyronine T3
Goiter - lack of iodine in diet
Why a goiter forms
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
Fig. 26.6
II. The Endocrine System
J. Thyroid
1. located just below larynx
2. Hormones produced (amine)
- Thyroxine T4
- Triidodthyronine T3
Goiter - lack of iodine in diet
Why a goiter forms
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
Fig. 26.6
II. The Endocrine System
J. Thyroid
1. located just below larynx
2. Hormones produced (amine)
- Thyroxine T4
- Triidodthyronine T3
Goiter - lack of iodine in diet
Why a goiter forms
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
Fig. 26.6
II. The Endocrine System
J. Thyroid
1. located just below larynx
2. Hormones produced (amine)
- Thyroxine T4
- Triidodthyronine T3
Goiter - lack of iodine in diet
Why a goiter forms
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
Fig. 26.6
II. The Endocrine System
J. Thyroid
1. located just below larynx
2. Hormones produced (amine)
- Thyroxine T4
- Triidodthyronine T3
Goiter - lack of iodine in diet
Why a goiter forms
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
Fig. 26.6
II. The Endocrine System
J. Thyroid
1. located just below larynx
2. Hormones produced (amine)
- Thyroxine T4
- Triidodthyronine T3
Goiter - lack of iodine in diet
Why a goiter forms
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
Fig. 26.6
II. The Endocrine System
J. Thyroid
1. located just below larynx
2. Hormones produced (amine)
- Thyroxine T4
- Triidodthyronine T3
Goiter - lack of iodine in diet
Why a goiter forms
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
Fig. 26.6
II. The Endocrine System
J. Thyroid
1. located just below larynx
2. Hormones produced (amine)
- Thyroxine T4
- Triidodthyronine T3
Iodized salt
Goiter - lack of iodine in diet
Why a goiter forms
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
J. Thyroid
1. located just below larynx
2. Hormones produced (amine)
- Thyroxine T4
- Triidodthyronine T3
3. Target Cells
- virutally all tissues
4. Actions
- childhood: bone and nerve cell
development
- Adulthood: Stimulate and maintain
metabolism in adults, maintain BP, heart
rate, muscle tone, digestion and
reproductive functions
Fig. 26.3
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
J. Thyroid
5. Disorders
i. hyperthyroidism
- too much T3 or T4
- overheating, excessive sweating,
irritable, high BP, weight lose
- Grave’s disease
- autoimmune disease
- antibodies made against TSH receptors
on thyroid
- Antibodies bind to receptors and
activate them in the absence of
TSH = hyperthyroidism
Fig. 26.3
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
J. Thyroid
5. Disorders
i. hyperthyroidism
- too much T3 or T4
- overheating, excessive sweating,
irritable, high BP, weight lose
- Grave’s disease
- autoimmune disease
- antibodies made against TSH receptors
on thyroid
- Antibodies bind to receptors and
activate them in the absence of
TSH = hyperthyroidism
antibodies
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
J. Thyroid
5. Disorders
i. hyperthyroidism
- too much T3 or T4
- overheating, excessive sweating,
irritable, high BP, weight lose
- Grave’s disease
- autoimmune disease
- antibodies made against TSH receptors
on thyroid
- activates receptors in absence
of TSH = hyperthyroidism
antibodies
20-25% of people with Graves' disease will suffer from Graves' ophthalmopathy (a protrusion of one or
both eyes), caused by inflammation of the eye muscles due to attacking autoantibodies.
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
I. Thyroid
E. Disorders
ii. hypothyroidism
- weight gain, lethargy, intolerance to
cold
- caused by defective gland or iodine
deficiency (goiter)
After hypothyroidism
before
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
I. Thyroid
E. Disorders
ii. hypothyroidism
- weight gain, lethargy, intolerance to
cold
- caused by defective gland or iodine
deficiency (goiter)
- Cretinism if occurring in childhood
a. retarded skeletal growth and poor
mental development
cretinism
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
2. Blood calcium homeostasis (10mg/100ml)
A. Some uses of calcium
i. Help neurons to transmit signals
ii. Muscle contraction
iii. Blood clotting (coagulation)
iv. Cotransport across PM
Cotransport occurs when a cell uses energy to
actively pump a substance like Ca++ or H+ across a
membrane resulting in an electrochemical gradient
similar to the pumping of H+ into the intermembrane
space of the mitochondria or into the thylakoid disk.
When the substance diffuses back passively, the
energy is used to transport another molecule with it
from low to high concentration (active) – therefore
your link facilitated diffusion with active transport.
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
2. Blood calcium homeostasis
(10mg/100ml in blood normally)
B. NOT UNDER HYPOTHALAMUS/PITUITARY
CONTROL
C. Hormones involved
i. Calcitonin
- secreted by thyroid
- lower blood Ca++
It is a polypeptide:
Fig. 26.3
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
2. Blood calcium homeostasis (10mg/100ml)
B. NOT UNDER HYPOTHALAMUS/PITUITARY
CONTROL
C. Hormones involved
i. Calcitonin (calcium in)
- secreted by thyroid
- lowers blood Ca++
ii. Parathyroid hormone (PTH)
- secreted by parathyroid glands
- raises blood Ca++
PTH (protein)
Fig. 26.3
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
2. Blood calcium homeostasis (10mg/100ml)
B. NOT UNDER HYPOTHALAMUS/PITUITARY
CONTROL
C. Hormones involved
i. Calcitonin
- secreted by thyroid
- lower blood Ca++
ii. Parathyroid hormone (PTH)
- secreted by parathyroid
- raises blood Ca++
**These are antagonistic hormones
(opposite effects)
Fig. 26.3
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
2. Blood calcium homeostasis (10mg/100ml)
B. NOT UNDER HYPOTHALAMUS/PITUITARY
CONTROL
C. Hormones involved
i. Calcitonin
- secreted by thyroid
- lower blood Ca++
ii. Parathyroid hormone (PTH)
- secreted by parathyroid
- raises blood Ca++
**These are antagonistic hormones
(opposite effects)
four embedded in thyroid
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
Fig. 26.7
II. The Endocrine System
2. Blood calcium homeostasis (10mg/100ml)
D. Mechanism of action
i. Calcitonin targets:
- bone, kidneys
ii. PTH targets:
- intestines, bone, kidneys
IMPORTANT: What you need to realize is that
the levels are ALWAYS fluctuating up and down
like a sinusoidal wave. This is a hallmark of
feedback. It never stays at 10mg/100ml and this
goes for the concentration of anything in your
body like protein levels in a cell or blood
glucose…. Nothing is static, everything is
dynamic.
four embedded in thyroid
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
2. Blood calcium homeostasis (10mg/100ml)
Fig. 26.7
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
2. Blood calcium homeostasis (10mg/100ml)
E. Vitamin D
i. sources
- food: cheese, butter, margarine, milk, fish,
cereal, etc…
- skin makes it when exposed to sun
ii. Activated in liver and kidney to become a
hormone (see figure)
iii. Kidney secretes activated form (Calcitriol)
- works with PTH
- targets bone and intestines similar to PTH
Vitamin D
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
3. Blood glucose regulation (90mg/100ml)
A. NOT UNDER HYPOTHALAMUS/PITUITARY
CONTROL
B. Pancreas
i. Endocrine and exocrine gland
Fig. 26.3
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
3. Blood glucose regulation (90mg/100ml)
A. NOT UNDER HYPOTHALAMUS/PITUITARY
CONTROL
B. Pancreas
i. Endocrine and exocrine gland
ii Islets of Langerhan
- endocrine portion
- made of alpha (α) and beta (β) cells
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
3. Blood glucose regulation (90mg/100ml)
C. Hormones involved
i. insulin
- produced by beta cells
- lowers blood glucose
insulin
ii. glucagon
- produced by alpha cells
- raises blood glucose
- Glucose is gone (glucagon…get it?)
glucagon
**These are antagonistic hormones
(opposite effects)
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
3. Blood glucose regulation (90mg/100ml)
D. Mechanism of action
i. Insulin targets:
- liver, body cells (fat cells,
muscle cells)
ii. Glucagon targets:
- liver
Hyperglycemia vs. Hypoglycemia
Fig. 26.8
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
3. Blood glucose regulation (90mg/100ml)
D. Mechanism of action
STORY:
You eat a candy bar or anything with carbs
and your blood sugar raises above
90mg/100ml. Proteins on the surface of
pancreatic beta cells located in the Islets of
Langerhan signal the beta cells to secrete
insulin (take glucose in) into the blood.
Insulin circulates and binds to insulin
receptors on hepatic (liver) cell, adipocytes
(fat cells), and myocytes (muscle cells).
Signal transduction occurs and the cells
send glucose transporter proteins to their
membranes. Glucose enters by facilitated
diffusion and is converted to glycogen in liver
and muscle, and to triglycerides in
adipocytes. The blood sugar levels drop
causing the beta cells to stop secreting
insulin.
Fig. 26.8
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
3. Blood glucose regulation (90mg/100ml)
D. Mechanism of action
STORY:
When they fall too low, the proteins on the
surface of pancreatic alpha cells also located
within the Islets of Langerhan send a signal
into the alpha cells causing them to secrete
glucagon (glucose is gone) into the blood.
Glucagon will circulate and bind to glucagon
receptors located on hepatocytes and
adipocytes causing them to breakdown
glycogen and release glucose. Why would
you not signal the myocytes to release
glucose? Because the muscles always need
the glucose to make ATP so they can
contract. Muscles do not store it for the body,
they store it for themselves. The blood sugar
levels rise causing the alpha cells to stop
secreting glucagon.
Fig. 26.8
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
3. Blood glucose regulation (90mg/100ml)
E. disorders
i. Diabetes mellitus
a. body cells do not absorb glucose (blood glucose high)
b. affects 5 out of 100 in US
c. 350,000 die from disease/year
d. Two types
1. Type I insulin dependent (early onset)
- autoimmune disease against beta cells
- don’t produce enough insulin
Insulin pump attached to user
- develops before age 15 typically
- insulin injection required
- genetically engineered (human insulin gene
put into a plasmid and inserted into bacteria)
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
3. Blood glucose regulation (90mg/100ml)
E. disorders
i. Diabetes mellitus
a. body cells do not absorb glucose (blood glucose high)
b. affects 5 out of 100 in US
c. 350,000 die from disease/year
d. Two types
1. Type II NON-insulin dependent (late or adult onset)
- faulty/missing insulin receptors on cells
- Insulin is being made just not being “seen”
- 90% of US cases are Type II
- typically develops after 40
- Treatment
- control sugar intake (diet)
- drugs that reduce glucose levels
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
3. Blood glucose regulation (90mg/100ml)
E. disorders
i. Diabetes mellitus
a. body cells do not absorb glucose (blood glucose high)
b. affects 5 out of 100 in US
c. 350,000 die from disease/year
d. Two types
1. Type II NON-insulin dependent (late or adult onset)
i. Cause
- Genetic predisposition combined with environmental triggers like
obesity, hypertension, elevated cholesterol, high fat diets and inactive
lifestyle.
ii. Treatment
- Managed by exercise and diet management
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
3. Blood glucose regulation (90mg/100ml)
E. disorders
i. Diabetes mellitus
a. body cells do not absorb glucose (hyperglycemia = blood glucose high)
b. affects 5 out of 100 in US
c. 350,000 die from disease/year
d. Type I and Type II
e. Result
- Cells don’t take up glucose resulting in high blood
glucose levels, burn fat/proteins instead
- Glucose seen in urine because kidneys can’t
take it out of the proximal tubule quick enough
- High glucose levels cause
Fig. 26.8
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
3. Blood glucose regulation (90mg/100ml)
E. disorders
i. Diabetes mellitus
Fig. 26.9
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
3. Blood glucose regulation (90mg/100ml)
E. disorders
ii. Hypoglycemia (low blood glucose level)
a. Beta cells secrete too much insulin
b. Diabetic takes too much insulin
c. Tumors that secrete insulin
d. Prolonged starvation
Treated by
-1. Increase meals with easily digestible carbs.
-2. More extreme cases can be treated with
medications like glucocoritcoids (steroid
hormones secreted by the adrenal cortex that
cause a rise in blood glucose) or
-3. part of the pancreas may need to be
surgically removed to reduce insulin secretion.
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
4. Mobilizing response to stress
A. Adrenal glands (two)
i. On top of each kidney – kidney hat
ii. Secrete hormones involved in the organisms
response to physical and/or emotional stress
iii. Two glands in one
Fig. 26.10
Fig. 26.3
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
4. Mobilizing response to stress
A. Adrenal glands (two)
i. On top of each kidney
ii. Secrete hormones involved in stress
iii. Two glands in one
1. Adrenal medulla
- central portion
Fig. 26.10
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
Fig. 26.10
II. The Endocrine System
4. Mobilizing response to stress
A. Adrenal glands (two)
i. On top of each kidney
ii. Secrete hormones involved in stress
iii. Two glands in one
1. Adrenal medulla
- central portion
- produces/secretes fight-or-flight
hormones
a. Epinephrine (adrenaline)
b. Norepinephrine (noradrenaline)
- responds to nerve signals (must be
rapid if you are in danger)
- short/term response, subsides rapidly
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
4. Mobilizing response to stress
A. Adrenal glands (two)
Fig. 26.10
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
Fig. 26.10
II. The Endocrine System
4. Mobilizing response to stress
A. Adrenal glands (two)
i. On top of each kidney
ii. Secrete hormones involved in stress
iii. Two glands in one
1. Adrenal medulla
2. Adrenal cortex
- outer portion
- slower, long lasting stress response
- responds to endocrine signals (ACTH from AP)
- Hormones released = corticosteroids (two types)
a. Mineralcorticoids
b. glucocorticoids
i. Cortisone (hydrocortisone) - suppresses inflammation,
typically given as an injection to an inflamed region like a
major joint (elbow or knee)
Chapter 3 - The Molecules of Cells
AIM: Describe the structure/function of lipids.
Corticosteroids
1. Glucocorticoids
a) Glucose Cortex Steroid
b)Regulate carbohydrate, fat and
protein metabolism
c) Anti-inflammatory affect –
reverse immune system activity after
infection is gone
d) ex. Cortisol and cortisone
(cortisone shots)
Chapter 3 - The Molecules of Cells
AIM: Describe the structure/function of lipids.
Corticosteroids
2. Mineralcorticoids
a) ex. Aldosterone
b) Helps to control salt (like sodium, which is a
mineral – ions required by biological systems) and
water levels in the body
c) Mineral cortex steroid
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
Fig. 26.10
II. The Endocrine System
4. Mobilizing response to stress
A. Adrenal glands (two)
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
5. Sex hormones
A. gonads
i. sex glands
- ovaries and testes
- secrete hormones in addition to gamete production
Fig. 27.2
Fig. 27.3
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
4. Sex hormones
A. gonads
i. sex glands
- ovaries and testes
- secrete hormones in addition to gamete production
ii. Sex hormones (3 categories) - all present in males AND females at different levels.
1. Estrogens
a. High in females compared to androgens
b. Maintain female reproductive system
c. Promote development of female secondary sex characteristics:
- smaller body size, higher pitch voice, breasts, wider hips
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
4. Sex hormones
A. gonads
i. sex glands
- ovaries and testes
- secrete hormones in addition to gamete production
ii. Sex hormones (3 categories) - all present in males AND females at different levels.
2. progestins
a. ex) progesterone
b. Prepare uterus to support the embryo
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
4. Sex hormones
A. gonads
i. sex glands
- ovaries and testes
- secrete hormones in addition to gamete production
ii. Sex hormones (3 categories) - all present in males AND females at different levels.
3. androgens
a. High in males compared to estrogens
- testosterone is the main one
b. Development and maintenance of male reproductive system
c. Promote development of male secondary sex characteristics:
- low-pitched voice, facial hair, large skeletal muscles
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
4. Sex hormones
A. gonads
i. sex glands
- ovaries and testes
- secrete hormones in addition to gamete production
ii. Sex hormones (3 categories) - all present in males AND females at different levels.
- estrogens, progestins, androgens
iii. Regulated by hypothalamus and AP
- FSH and LH
FLAGTEP
Fig. 26.5
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System
4. Sex hormones
B.Steroid Biosynthesis
(just for fun)
Chapter 26: Regulation Part I - The Endocrine System
AIM: How do chemical signals coordinate body functions?
II. The Endocrine System