Endocrine
System
Anatomy of the Endocrine System
Which organs did you
not expect to be
included as endocrine
organs?
List some of the general
functions of hormones.
Pituitary
Gland
(See similar figure in your packet)
Why is this gland
considered an
important link
between the nervous
and endocrine
systems?
What is a tropic
hormone?
Hypothalamic Control of
Endocrine Organs
How do these regulatory
hormones get to the
adenohypophysis?
Sympathetic or
Parasympathetic?
Hypothalamic Regulation of
Endocrine Glands
HYPOTHALAMUS
(neurons)
Body Temp.
Blood nutrients
Water balance
Blood pressure
Emotional state
Etc.
releasing/
inhibiting
hormones
*
NEUROHYPOPHYSIS
(neuron axons)
 in
HYPOPHYSEAL
PORTAL VEINS
ADENOHYPOPHYSIS
(glandular portion)
Condition
= negative feedback
* = neuron firing
This figure is also found in your course packet.
Hypothalamic Regulation of Blood
Glucose Between Meals
(A negative feedback mechanism via the hypothalamus)
Normal Blood Glucose
(80-110mg/dl)
BS
BS
LIVER
HYPOTHALAMUS
(gluconeogenesis)
Cortisol
CRH
ADRENAL CORTEX
ANTERIOR PITUITARY
ACTH
Neurosecretory Cells in the
Hypothalamus
Name at least 3 hormones involved in regulating water balance.
The neurohypophysis
develops from:
a) Telencephalon
b) Diencephalon
c)
Mesencephalon
d) Rhombencephalon
Hypothalamic Regulation of
Water Balance
Normal Water Balance
Water
Voluntary water intake
KIDNEY
ECF, ICF
(Dehydration)
HYPOTHALAMUS
(Osmoreceptors)
Antidiuretic Hormone
(Vasopressin)
NEUROHYPOPHYSIS
(Posterior pituitary)
This figure is also found in your course packet.
Thyroid
Gland
Which mineral is
essential in the
production of
hormones from
thyroid follicles?
What is
thyroglobulin?
Which endocrine cells
produce
thyrocalcitonin?
Parathyroid
Glands
Describe the complete
homeostatic mechanism
involving parathyroid
hormone and thyrocalcitonin.
Why is calcium regulation so
important to body function?
(Name at least 3 functions of
Ca+2.)
Cells of the adrenal
cortex are derived from
mesoderm. Where are
the cells of the adrenal
medulla from?
Adrenal
Glands
How is hormone
release from the
adrenal cortex
controlled? … from the
adrenal medulla?
Renin-Angiotensin-Aldosterone System
in the Regulation of Water Balance
Normal Blood Volume/ Normal BP
Na+ , Water
K+ ,
Na+
KIDNEY
BP
KIDNEY
Aldosterone
(plasma)
Renin
(plasma)
ADRENAL CORTEX
(Zona Glomerulosa)
ACE
Angiotensin II
Angiotensin I
Vasoconstriction ( BP, and venous return)
Stimulates ADH release
Thirst
This
Angiotensinogen
figure is also found in your course packet.
Pancreas
The pancreas also
has an exocrine
function. Where
are these products
released?
Describe the
overlapping
homeostatic
mechanisms
involving insulin
and glucagon.
Glucose Homeostasis
Reproductive Glands
Ovarian hormones
include estrogens,
progesterone, relaxin
and inhibin.
The testes produce
testosterone and inhibin.
(Table 23.8)
The placenta also
produces estrogen and
progesterone. Why?
Other Endocrine Tissues and
Their Secretions
• Pineal gland: Melatonin
– What is the significance of its location near the
thalamus?
– Why is it significant that this gland is innervated by
sympathetic nerves?
• Thymus gland: Thymosin
– What effect might a reduction in thymosin production
have on one’s ability to defend against disease?
• Adipocytes: Leptin
– How is obesity hypothesized to be related to early
puberty?
… Continued
• Heart: Atrial Natriuretic Peptide (ANP)
– What does the name of this hormone tell you about its
action?
• Stomach: Gastrin
– Briefly describe the positive feedback mechanism
involving Gastrin
• Kidneys: Erythropoietin
– What is the target tissue for this hormone?