NUR 612 EXAM 1
1. Endocrine System: System composed of various glands that can
synthesize and release special chemical messengers called
hormones.
System works closely with the Nervous System and the Immune system
to regulate and integrate body functions.
Functions:
Growth and
development Sexual
differentiation
Metabolism
Adaptation to an ever-changing
environment Regulation of digestion
Use and storage of nutrients
Electrolyte and water
metabolism Reproductive
functions
2. Hormones: Endocrine system uses chemical substances called
hormones as a means of regulating and integrating body functions.
Hormones are thought of as chemical messengers produced to target
a specific cell. They do NOT initiate reactions but function as a
modulator of cellular and systemic responses.
Function as chemical messengers
Move through the blood to distant target sites of action
Or, act more locally as paracrine or autocrine messengers that incite
more local effects
Most are present in body fluids at all times in greater or lesser amounts
as needed. Characteristics
A single hormone can exert various effects in different
tissues. A single function can be regulated by several
hormones.
,3. Types of Hormone Actions: Hormones are released in one location
but can have the biologic effect either in that location of release or
somewhere else Endocrine
Paracrin
e
Autocrin
e
Intracrin
e
4. Endocrine: Hormones are released in the circulation to act on a
target organ (between remote cells)
,5. Paracrine: Hormones acts locally in cells other than that produced
the hor- mones Ex: sex steroids in ovary (between local cells)
Hormones acting locally on cells other than those that produced
the hormone For example, the action of sex steroids on the ovary
6. Autocrine: Hormones exert action on the cells from which they are
produced ex: insulin (on the cell that produced them)
Hormones exerting action on the cells from which they were produced
For example, the release of insulin from pancreatic beta cells can
inhibit its release from the same cells
7. Intracrine: Hormone action is within the cell that produced the hormon
8. Mechanisms of Hormone Action: Hormones interact with high-affinity
recep- tors.
These are linked to one or more effector system in the cell.
Hormone receptors may be located in the plasma membrane of the
cell (surface of the cell) or in the intracellular compartment (inside
the cell) of the target cell.
9.The vesicle mediated pathway: Protein and polypeptide hormones are
synthe- sized and stored in vesicles in the cytoplasm of the endocrine
cell until secretion is required. Stimulation of the endocrine cell causes
the vesicles to move to the cell membrane and release their
hormones.
10.Non-vesicle mediated pathway: Hormones are synthesized in the
smooth endoplasmic reticulum and released upon synthesis. Ex.:
Steroid hormones
11.Actions of Hormones Released into the Bloodstrea:mCirculate as
free, unbound molecules
Peptide hormones and protein hormones usually circulate unbound in th
blood. Circulate as hormones attached to transport carriers
Steroid hormones and thyroid hormone are carried by specific
carrier proteins synthesized in the liver.
Intracellular and extracellular mechanisms participate in the
termination of hor- mone function.
Only free hormones can signal a target cell.
12.Important Thoughts on Transport Carrier Hormone: sThe extent of
hor- mone binding to it's transport carrier influences the rate at which
, hormones leave the blood and enter the cells.
Pause and read Transport at the bottom of page 1265 through mid-
page 1267. Understand the correlation between hormone binding
and half-life.
1. Endocrine System: System composed of various glands that can
synthesize and release special chemical messengers called
hormones.
System works closely with the Nervous System and the Immune system
to regulate and integrate body functions.
Functions:
Growth and
development Sexual
differentiation
Metabolism
Adaptation to an ever-changing
environment Regulation of digestion
Use and storage of nutrients
Electrolyte and water
metabolism Reproductive
functions
2. Hormones: Endocrine system uses chemical substances called
hormones as a means of regulating and integrating body functions.
Hormones are thought of as chemical messengers produced to target
a specific cell. They do NOT initiate reactions but function as a
modulator of cellular and systemic responses.
Function as chemical messengers
Move through the blood to distant target sites of action
Or, act more locally as paracrine or autocrine messengers that incite
more local effects
Most are present in body fluids at all times in greater or lesser amounts
as needed. Characteristics
A single hormone can exert various effects in different
tissues. A single function can be regulated by several
hormones.
,3. Types of Hormone Actions: Hormones are released in one location
but can have the biologic effect either in that location of release or
somewhere else Endocrine
Paracrin
e
Autocrin
e
Intracrin
e
4. Endocrine: Hormones are released in the circulation to act on a
target organ (between remote cells)
,5. Paracrine: Hormones acts locally in cells other than that produced
the hor- mones Ex: sex steroids in ovary (between local cells)
Hormones acting locally on cells other than those that produced
the hormone For example, the action of sex steroids on the ovary
6. Autocrine: Hormones exert action on the cells from which they are
produced ex: insulin (on the cell that produced them)
Hormones exerting action on the cells from which they were produced
For example, the release of insulin from pancreatic beta cells can
inhibit its release from the same cells
7. Intracrine: Hormone action is within the cell that produced the hormon
8. Mechanisms of Hormone Action: Hormones interact with high-affinity
recep- tors.
These are linked to one or more effector system in the cell.
Hormone receptors may be located in the plasma membrane of the
cell (surface of the cell) or in the intracellular compartment (inside
the cell) of the target cell.
9.The vesicle mediated pathway: Protein and polypeptide hormones are
synthe- sized and stored in vesicles in the cytoplasm of the endocrine
cell until secretion is required. Stimulation of the endocrine cell causes
the vesicles to move to the cell membrane and release their
hormones.
10.Non-vesicle mediated pathway: Hormones are synthesized in the
smooth endoplasmic reticulum and released upon synthesis. Ex.:
Steroid hormones
11.Actions of Hormones Released into the Bloodstrea:mCirculate as
free, unbound molecules
Peptide hormones and protein hormones usually circulate unbound in th
blood. Circulate as hormones attached to transport carriers
Steroid hormones and thyroid hormone are carried by specific
carrier proteins synthesized in the liver.
Intracellular and extracellular mechanisms participate in the
termination of hor- mone function.
Only free hormones can signal a target cell.
12.Important Thoughts on Transport Carrier Hormone: sThe extent of
hor- mone binding to it's transport carrier influences the rate at which
, hormones leave the blood and enter the cells.
Pause and read Transport at the bottom of page 1265 through mid-
page 1267. Understand the correlation between hormone binding
and half-life.
