Physiology of Introduction to endocrinology & communication. Cell to Cell Communication. Prof. Dr. Rashid Mahmood

1. Introduction to Cell Communication & Endocrinology
Prof. Dr. Rashid Mahmood

2. 1/5/2019 Presentation Title | Presented By: Name 2
Introduction to Cell Communication &Endocrinology

3. Objectives
•By the end of this session students should be able
to
•Differentiate various modes of Types of cell-to-cell
signaling/ Communication
•Describe the overall workings of the endocrine
system.
•Explain the factors that determine whole-body3© Prof. DR. Rashid Mahmood

4. 4
Definitions
• Neurotransmitters
• are released by axon terminals of
neurons into the synaptic
junctions and act locally to control
nerve cell functions.
© Prof. DR. Rashid Mahmood

5. 5
Definitions
• Neuromodulators
• are substances that are not
neurotransmitters but affect the
activity of the neurotransmitters
© Prof. DR. Rashid Mahmood

6. 6
Definitions
•Hormone
•Chemical substance
•Produced by a cell or a group of cells
•Secreted into body fluids
•Carried by body fluids to site of action (Target)
•Acts on other tissues to regulate their functions
•It may be an Endocrine hormone,
Neuroendocrine hormone, Paracrine, Autocrine
or a Cytokines
© Prof. DR. Rashid Mahmood

7. 7
Definitions
• Endocrine hormones
• are released by glands or
specialized cells into the
circulating blood and influence
the function of cells at another
location in the body.
© Prof. DR. Rashid Mahmood

8. 8
Definitions
• Neuroendocrine
hormones
• are secreted by neurons into the
circulating blood and influence the
function of cells at another location
in the body.
© Prof. DR. Rashid Mahmood

9. 9
Definitions
• Paracrines
• are secreted by cells into the
extracellular fluid and affect
neighboring cells of a different type.
© Prof. DR. Rashid Mahmood

10. 10
Definitions
• Autocrines
• are secreted by cells into the
extracellular fluid and affect the
function of the same cells that
produced them by binding to cell
surface receptors.
© Prof. DR. Rashid Mahmood

11. Definitions
•Cytokines
•Cytokines are peptides secreted by cells into
the extracellular fluid and can function as
Autocrines, Paracrines, or endocrine hormones.
•Examples
•interleukins
•Cytokine hormones (e.g., leptin) produced by
adipocytes are sometimes called adipokines.
11© Prof. DR. Rashid Mahmood

12. 12
neurotransmitter
Hormone
© Prof. DR. Rashid Mahmood

13. Assessment Q.1
• A substance ‘X’ is secreted by a neuron in a
tissue ‘A’. It then enters the blood & performs its
action in tissue ‘B’.
• What substance is this?
A. Autocrine
B. Paracrine
C. Neuroendocrine hormone
D. Endocrine hormone
E. Neurotransmitter
Introduction to Cell Communication &Endocrinology
| © Prof. Dr. Rashid Mahmood 13
C

14. 1/5/2019 Presentation Title | Presented By: Name 14
Modes of Types of cell-to-cell
signaling/ Communication

15. Cell Communication
•The study of cell communication
focuses on how a cell gives and
receives messages with its
environment and with itself
Presentation Title | Presented By: Name 151/5/2019

16. Study of cell signaling
•In order to respond to changes in their
immediate environment, cells must be
able to receive and process signals that
originate outside their borders
Introduction to Cell Communication &Endocrinology
| © Prof. Dr. Rashid Mahmood 16

17. Cell Communication & Cell signaling
Introduction to Cell Communication &Endocrinology
| © Prof. Dr. Rashid Mahmood 17
Cells do not live in isolation
Cells communicate directly with one another — and
change their own internal workings in response
Individual cells often receive many signals
simultaneously, and they then integrate the information
they receive into a unified action plan

18. Are cells targets for receiving signals?
Introduction to Cell Communication &Endocrinology
| © Prof. Dr. Rashid Mahmood 18
Cells aren't just targets. They also send out messages to
other cells both near and far.
Cell can also communicate directly with another and change
their own internal workings in response- by way of variety of
chemical and mechanical signals
In multicellular organisms. Cell signaling
allows for specialization of groups of cells

19. Types of cell-to-cell signaling/ communication
19© Prof. DR. Rashid Mahmood

20. Types of Intercellular Communications
20

21. Control of body functions
• Nervous system
• Hormones
Skeletal muscles
Visceral functions
5-Jan-19 Autonomic Nervous System | © Prof. Dr. Rashid Mahmood 21
Interrelationship between the two systems
Hypothalamus

22. Two control systems
• Nervous system
• General somatic control
• Locomotor control
• Somatic & Visceral nervous
reflexes
• Perception of
environmental changes
• Response to these changes
• Endocrine system
• Metabolic functions
• Chemical or biochemical
reactions
• Growth development
• Transport across the CM
• Secretions
• Reproduction
• Behavior
22
Interrelationship between the two systems
Hypothalamus
© Prof. DR. Rashid Mahmood

23. Introduction of Endocrinology
• Study of specialized glands in body & their specific
secretions known as hormones and their related effects
on the body.
• This system provides a mean of communication that
keeps the body with in a constant internal
environment.
• It is an essential for the survival and adaptation of
human body through-out life.
• In nutshell it balances health and disease.

24. Importance of Endocrinology
• Around 10% of world population suffers from
Endocrine disorder.
• Diabetes holds about 8.5%
• In Pakistan out of 200 million, 10% suffer from
iodine deficiency manifestation of thyroid and
mental disorders
• Secondary hypertension maybe due to many
hormonal disorders
Understanding and management of endocrine related disease is based on full
comprehension of structure, function and biochemical composition / changes.

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Overall workings of the
endocrine system

26. 26
Different
endocrine
glands Heart
Placenta© Prof. DR. Rashid Mahmood
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2
3
4
5
6
7
10
9
8
11
12
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27. Assessment Q. 2
• Functioning of Skeletal muscles is controlled by
A. Somatic nervous system
B. Autonomic nervous system
C. Endocrines
D. Nervous system
E. All of the above
Presentation Title | Presented By: Name 271/5/2019
A

28. 1/5/2019 Presentation Title | Presented By: Name 28
Factors that determine
whole-body responsiveness
to hormones (& neurotransmitters)

29. Factors that determine whole-body
responsiveness to hormones (&
neurotransmitters)
1/5/2019 Presentation Title | Presented By: Name 29
External
environment
like
Temperature
Internal
environment like
changes in ionic
concentration
Input to endocrine Glands (&
Nervous System)

30. Inputs to endocrine cells (& Neurons)
© Prof. DR. Rashid Mahmood 30

31. 31
Mechanism of action of
Hormones
(& Neurotransmitters)

32. A cell is a target because is has a
specific receptor for the hormone
© Prof. DR. Rashid Mahmood 32

33. 33
Hormone
Receptor
Cell membrane
(surface/ inside)
Inside cell
(Cytoplasm/
Nucleus)
HR Complex (Change in function of cell)
Direct action 2nd
Messenger
System
Action on Genetic Machinery
Ion
channels
_Linked
receptors
G-Proteins-
Linked
Receptors
Enzyme-
linked
receptors
Activation of genes
cAMP
Phspholipase C
Ca++-Calmodulin
Protein synthesis
Gene transcription
1
2 3
4
5
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7

34. 34
Hormone
Receptor
Cell membrane
(surface/ inside)
Inside cell
(Cytoplasm/
Nucleus)
HR Complex (Change in function of cell)
Direct action 2nd
Messenger
System
Action on Genetic Machinery
Ion
channels
_Linked
receptors
G-Proteins-
Linked
Receptors
Enzyme-
linked
receptors
Activation of genes
cAMP
Phspholipase C
Ca++-Calmodulin
Protein synthesis
Gene transcription
1
2 3
4
5
6
7

35. Assessment Q. 3
• Receptors for Hormones & neurotransmitters
may be located
A. Cell membrane surface
B. Inside cell membrane
C. In Cytoplasm
D. In Nucleus
E. All of the above
Presentation Title | Presented By: Name 351/5/2019
E

36. 36
1. Open vs Closed Acetylcholine Channels
(Ion Channel-Linked Receptor)
Open
Closed

37. 2. G- Protein activation

38. 38
7. Calmodulin
 HR complex
 Opening of Ca++ channels
 Combination of Calmodulin with up to 4 Ca++
 Activation of protein kinase
 Activation or inactivation of different enzymes
 e.g. myosin kinase which then causes smooth
muscle contraction

39. Summary
•Endocrines are one of the TWO controlled systems
of the body
•A hormone is a chemical substance produced by a
cell or a group of cells, secreted into body fluids
and carried by body fluids to the target organ to
act on other tissues to regulate their functions
•Many external & internal factors determine the
whole-body responsiveness to hormones, like
temperature, changes in ionic concentration of© Prof. DR. Rashid Mahmood 39

40. Learning Resources
•Guyton and Hall (Text book of physiology), 13th
Edition
•Human Physiology : from cells to system Lauralee
Sherwood,9th Edition
•Ganong (Text book of physiology), 25th Edition
•Berne & Levy Principles of Physiology (Koeppen
BM), 7th Edition
•Human Physiology Stuart Ira Fox, 13th Edition
•Internet © Prof. Dr. Rashid Mahmood 40

41. Assessment Q. 4
• What is the latest edition of Guyton and Hall Text
book of physiology?
• Name any TWO Physiology books other than
Guyton and Hall Text book of physiology.
Presentation Title | Presented By: Name 411/5/2019
13th

42. Thank You
Questions/ Comments?
rashid.mahmood@rmi.edu.pk
drrashid62&@gmail.com