Download Chapter 16: Endocrine System

Endocrine System
Page 345 Textbook – old Martini/Bartholomew book
Page 586 Textbook – new Amerman book
Page 3 Coursepack
Controlling Systems of the Body
• Nervous System
– Faster
– Uses neurotransmitters
• Endocrine System
– Slower
– Uses hormones
How are hormones different
from neurotransmitters?
How Do Exocrine Glands Differ
from Endocrine Glands?
Exocrine Gland (Sweat Gland)
Endocrine Gland (Thyroid Gland)
Major Endocrine Glands
What are hormones?
Hormones are chemical
messengers that travel through
the blood stream to target areas.
Two Chemical
Classifications of Hormones
• Amino acid-based (protein)
• Steroids (lipid)
Review of
Plasma Membrane Structure
How do Hormones
Arouse their Target Cells?
Target cells must have a receptor for the hormone
Two methods:
• Secondary messenger system (proteins)
• Direct gene activation (lipids)
Secondary Messenger System –
Protein-based Hormones
Direct Gene Activation – Steroid-based Hormones
Hormone Interactions
• Permissiveness
• Synergism
• Antagonism
Control of Hormone Release
• Humoral stimuli
• Ion or nutrient concentration (in blood) stimulates
hormone release
• Neural stimuli
• ANS stimulates hormone release from nerves
• Hormonal stimuli
• One hormone stimulates the release of another
hormone
Hypothalamus – Makes and Releases
Releasing hormones (RH) & Inhibiting hormones (IH)
To target the Anterior Pituitary Gland
Hypothalamus Hormones
•
•
•
•
•
•
•
Growth Hormone Releasing Hormone (GHRH)
Growth Hormone Inhibiting Hormone (GHIH)
Thyroid Releasing Hormone (TRH)
Corticotropic Releasing Hormone (CRH)
Gonadotropic Releasing Hormone (GnRH)
Prolactin Releasing Hormone (PRH)
Prolactin Inhibiting Hormone (PIH)
RULE #1
Releasing hormones (RH) and
inhibiting hormones (IH)
made by the hypothalamus
will target the anterior pituitary
Hypothalamus
• Makes and releases
releasing (-RH) and
inhibiting hormones
(-IH) to target the
anterior pituitary
• Makes OXY and ADH
• Stores these hormones
in axon terminals in the
posterior pituitary until
they are released
• The posterior pituitary
is responsible for
releasing OXY and ADH
Hypothalamus & Pituitary Gland Relationship & Location
Anterior Pituitary Hormones
(–SH and –TH hormones)
•
•
•
•
Growth Hormone
Thyroid Stimulating Hormone (TSH)
Adrenocorticotropic Hormone (ACTH)
Gonadotropins
– Follicle Stimulating Hormone (FSH)
– Luteinizing Hormone (LH)
• Prolactin (PRL)
RULE #2
Stimulating hormones (SH) & some
tropic hormones (TH) are made by
the anterior pituitary gland
Tropic Hormones
• Tropic hormones stimulate other glands of the
body to produce hormones
• Some tropic hormones are produced by the
anterior pituitary gland
– Thyroid stimulating hormone (TSH) is a tropic
hormone because it stimulates the thyroid gland
to produce a hormone called thyroxine
Anterior Pituitary Hormones
are Proteins
Growth Hormone (GH)
• Target: all cells of the body, especially
bones, skeletal muscles, and liver
• Functions:
–Increase size of body cells
–Growth of muscle and bone tissue (and
liver)
• Did you know? Levels increase when
we sleep
Flow Chart for Growth Hormone
Hypothalamus produces GHRH
GHRH targets the anterior pituitary
Anterior pituitary produces GH
GH targets the body’s cells
Body cells grow (enlarge in size)
Control of GH secretion
• Growth hormone-releasing hormone
(GHRH) promotes GH release
• Growth hormone-inhibiting hormone
(GHIH or somatostatin) inhibits GH
release
Cell Cycle and Growth Hormone
Growth Hormone Disorders
• Gigantism / Giantism – excess or
hypersecretion of GH (child)
• Acromegaly – excess or hypersecretion of
GH (adult)
• Pituitary Dwarfism – too little or
hyposecretion of GH (child)
Gigantism
Normal
Normal
Pituitary
Dwarfism
Andre the Giant
Had
Both
Gigantism And
Acromegaly
Sandy Allen-was the
tallest woman until
her death in 2008
• Yao Ming
• 7’ 6”
• Robert
Wadlow
8’ 11”
Tallest
man in
recorded
history
• 1918-1940
Died from
a blister
caused by
his leg brace!
Acromegaly
Acromegaly
Acromegaly
Acromegaly
More acromegaly
Far Left: Cretinism, hypothyroidism (notice disproportionate body)
Next two, Pituitary Dwarfs (notice proportions are correct)
Next two could be achondroplasic dwarfs (notice disproportionate size
of extremities)
Quick Review!
• Hormones that have the same effect when
working together are exemplifying:
A.
B.
C.
D.
E.
Synergism
Permissiveness
Antagonism
Both Synergism and Permissiveness
Both Synergism and Antagonism
Quick Review!
• Calcitonin and PTH perform opposite
actions from one another while regulating
blood calcium levels. They are:
A.
B.
C.
D.
E.
Synergists
Antagonists
Permissive
Responding to hormonal stimuli
Responding to neural stimuli
Quick Review!
• A hormone that uses the secondary messenger
system is (select all that apply):
____Assembled from cholesterol
____Composed of amino acids
____Activating protein kinases via cAMP
____Able to diffuse across the plasma membrane
____Docking with an intracellular receptor
____Promoting protein synthesis within the cell
On a piece of paper…
1. Outline how the secondary messenger
system operates
2. Explain how the hypothalamus controls the
release of hormones from the anterior
pituitary gland.